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Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Picked up a 1989 Firebird for the wife. It ran ok but not great. Wife sent it to her friend's the body shop and after a 6 month crapshow I got the car back from them not running, they were also nice enough to steal the radio out of the car so dash wiring looks life garbage now. It was a no crank/no start initially but the neutral safety switch appeared to be the issue. Now it's got good spark from the coil and spark to the plugs (but not what I'd consider strong spark to the plugs). Fuel flow confirmed before the rail and fuel pressure at the rail shows 35psi. Ran a noid light on all 8 injectors and they don't light up when the ignition key is in run put pulse when I turn it over and attempt to start it. I sprayed a small amount of starting fluid into the intake and it starts briefly so I'm obviously leaning towards a fueling issue but like I said, I don't love the spark I'm seeing at the plugs either. Any help is appreciated.
I originally thought it was the VATS, when I had no crank/no start so I bypassed it. I'm not saying it's not the problem but what I've read is that if the security light goes off 5 seconds after turning the key and the fuel injectors are firing the VATS is functioning.
How many shorted injectors shorted would it take for this era 5.7 not to start?
With the poor spark I was going to replace the distributor cap/rotor and then saw with the price of cap/rotor and ICM a whole distributor was only a few bucks more. I don't know the history of the distributor in this car and so I'll play it safe and swap it out tomorrow.
Thanks
Some quick tests, unplug all injector leads check for injector pulse. All it takes is one shorted injector to shut down the injector driver. Vats can still crank and not give 30hz from passkey module to ecm. Pull down the ecm
Check for 30hz at 50-60% at blue wire pin b6 at the ecm.
When you're saying check for injector pulse, you mean differently than with a noid light?
I swapped the distributor this morning so ICM should be out as a cause. Also forgot to mention it's not showing any codes on the OBD-1.
I'll pull the ECM and check the voltage on it. I'd love to just swap in some new injectors but that's an all day job with this car's over-engineered design so it'd be at least a couple weeks before I'd have the free time to do that
Some quick tests, unplug all injector leads check for injector pulse. All it takes is one shorted injector to shut down the injector driver. Vats can still crank and not give 30hz from passkey module to ecm. Pull down the ecm Check for 30hz at 50-60% at blue wire pin b6 at the ecm.
You check the hertz at pin B6 with the ECM plugged in and the key in the run position or key off? Because I'm getting 550hz at 60% at pin B6 with the ECM unplugged and the key in run.
Last edited by dilligaf13; 09-28-2023 at 06:23 PM.
Ran a noid light on all 8 injectors and they don't light up when the ignition key is in run put pulse when I turn it over and attempt to start it.
Originally Posted by Tuned Performance
Some quick tests, unplug all injector leads check for injector pulse. All it takes is one shorted injector to shut down the injector driver. Vats can still crank and not give 30hz from passkey module to ecm. Pull down the ecm
Check for 30hz at 50-60% at blue wire pin b6 at the ecm.
If the noid light flashes when turning over, the injectors are given some sort of command. Are we sure the VATs is the right direction?
Two quick and common things that come to my mind, and have been my own experience is A) Bad injectors since this is a 1989 or B) Failed ECT making the fuel mixture way off for cold start.
Jt I was under the assumption his answers no injector pulse. Maybe I missed the response. Or op were you saying all injectors unplugged you had pulse ? You said go to go ?
Yes, I got pulse on the noid light at all 8 injectors.
So based on the measurements at ECM pin 6, I'm guessing the VATS system isn't functioning correctly. Is there anything else in the VATS system other than the VATS control module that could be creating this problem?
"Two quick and common things that come to my mind, and have been my own experience is A) Bad injectors since this is a 1989 or B) Failed ECT making the fuel mixture way off for cold start."
By ECT you mean Engine Coolant Temperature Sensor? I'm not getting it to even want to start with starting fluid at this point so I'm not leaning towards the fuel injectors as much anymore. I definitely want to change them but in GM's imminent wisdom of making it such a PITA in these cars I'd like to eliminate all the smaller stuff first.
So based on the measurements at ECM pin 6, I'm guessing the VATS system isn't functioning correctly. Is there anything else in the VATS system other than the VATS control module that could be creating this problem?
"Two quick and common things that come to my mind, and have been my own experience is A) Bad injectors since this is a 1989 or B) Failed ECT making the fuel mixture way off for cold start."
By ECT you mean Engine Coolant Temperature Sensor? I'm not getting it to even want to start with starting fluid at this point so I'm not leaning towards the fuel injectors as much anymore. I definitely want to change them but in GM's imminent wisdom of making it such a PITA in these cars I'd like to eliminate all the smaller stuff first.
If you're getting noid activity on the injectors during cranking, the ECM is pulsing the injectors for fuel delivery. I don't think your VATs is involved. The VATs will simply tell the ECM to not fire the injectors. That doesn't sound like your issue.
My suggestion was based on you also saying you could get it to run with starting fluid. Now you're saying that's not working as well. ECT is Engine Coolant Temperature sensor and it's used to help set the initial fuel mixture.
Two runners, plenum, throttle body. Four bolts hold the rails down and the injectors come right out. Not really that big of a deal? Buy new gaskets and if you don't like torx then you can get stainless internal hex bolt kits on ebay.
So is the VATS system a "pass/fail" system? Meaning if the system doesn't receive the proper Ohms from the pass key it doesn't send the resistance to the ECM and the ECM in turn doesn't send voltage to the starter and the fuel injectors? so basically, is this an all or nothing VATS system where it would receive either no voltage to the starter/fuel injectors or the correct voltage?
So is the VATS system a "pass/fail" system? Meaning if the system doesn't receive the proper Ohms from the pass key it doesn't send the resistance to the ECM and the ECM in turn doesn't send voltage to the starter and the fuel injectors? so basically, is this an all or nothing VATS system where it would receive either no voltage to the starter/fuel injectors or the correct voltage?
Per the book, the injector duty time can vary from 1-4 m/s.
I still think you may have more than one issue, based on your initial comment that it started and ran on starting fluid but then you said that's not working.
1. Starting on starting fluid suggests a fuel issue. Could be the injectors are not flowing because they're clogged or they've failed. The multec injectors are known for this. Your tests may not show this unless you ohm each injector but that won't rule out clogged injectors.
2. Not starting on starting fluid suggests an ignition issue.
This assumes that the basics, such as timing and normal compression, are correct and present.
I also wouldn't rule out a failed ect and making the ECM lookup the wrong starting and running air/fuel ratio via injector duty cycle. The only way to know this is to either ohm the sensor and look at its value compared to temperature or get the tools to connect to the ECM and view the limited live data, which ect is one of those available.
Originally Posted by dilligaf13
I used a Powerprobe and tested the power to 2 of the fuel injectors so far. I'm showing same in each as:
On time 4.15 m/s
Inductive Kick 78.3
ECM ground voltage 1.28
Injector voltage 9.8
Voltage is obviously low and I don't like the ground voltage. I'm going to check my ground but can anything other than the ECM cause this?
Per the book, the injector duty time can vary from 1-4 m/s.
I still think you may have more than one issue, based on your initial comment that it started and ran on starting fluid but then you said that's not working.
1. Starting on starting fluid suggests a fuel issue. Could be the injectors are not flowing because they're clogged or they've failed. The multec injectors are known for this. Your tests may not show this unless you ohm each injector but that won't rule out clogged injectors.
2. Not starting on starting fluid suggests an ignition issue.
This assumes that the basics, such as timing and normal compression, are correct and present.
I also wouldn't rule out a failed ect and making the ECM lookup the wrong starting and running air/fuel ratio via injector duty cycle. The only way to know this is to either ohm the sensor and look at its value compared to temperature or get the tools to connect to the ECM and view the limited live data, which ect is one of those available.
Replaced the ECT and re-replaced the coil this morning and no change. Ohms at both ECTs were the same, IIRC voltage was around 5 volts at the ECT plug. Same values at the Fuel injector plugs as before of ECM ground voltage at 1.28 and Injector voltage at 9.8.
Replaced the ECT and re-replaced the coil this morning and no change. Ohms at both ECTs were the same, IIRC voltage was around 5 volts at the ECT plug. Same values at the Fuel injector plugs as before of ECM ground voltage at 1.28 and Injector voltage at 9.8.
Should have said it's best to test parts before replacing. I'm sure we have a post somewhere with some temp vs ohm points or could have provided it.
I'm not sure how you're measuring the voltage and ground voltage, but know that testing it wrong can not only show wrong results but it can damage the ECM.
Everyone is going to have their own method, but I suppose I'd start pulling spark plugs and checking their condition. Are they wet (too much fuel and/or no ignition) or dry? Are they clean enough to ignite? You said starting fluid isn't working like it did so that's why I'd look at those. It also sounds like it has sat for a long time and came to you, so do you know if it did run good before? How's the gas and fuel pressure? Again, the information you've posted suggests more than one issue. You may need to ohm each injector to see if any one or more has electrically failed as the multecs are known for that.
I'm using a Power Probe 4 which specifically has a fuel injector testing function.
2 of the fuel injectors tested at 12.3 and 13.1 ohms so I replaced all the fuel injectors and there's no change. I've never seen a car run less than 12 volts at the fuel injector plug so I still can't see how this car is supposed to run at less than 10 volts to the plugs. I took some of the gas that I pumped out confirming fuel pressure to the rail and it burned in the old fire pit pretty well...
I've replaced the distributor/ICM, coil, ECT, and fuel injectors. I'll try to change the plugs and wires tomorrow but I find it highly unlikely that a few months of sitting caused the plugs to just stop working.... Other than the plugs what else is left besides the ECM on these cars (and is it the ECM, prom, or both)?
Last edited by dilligaf13; 10-01-2023 at 09:10 PM.
GM's service manual says injectors should be 10 ohm minimum and no more than 1 ohm difference between them all. I've seen other notes that it should be closer to 15 ohm.
No, you should have battery voltage (12 volt) to the injectors with key on. The ECM provides the ground that turns the injectors on and off.
Check the voltage on Injector 1 and Injector 2 fuses inside the car. You should have battery voltage (12 volt) there. It gets its feed from the ignition switch. If you got 12 volt at the fuses but less than that at the injector harness, then maybe you've got a wiring issue. However, Injector 1 and Injector 2 fuse feed one bank, individually, so the odds of both circuits have an issue are in question. However, they both share the same supply from the ignition switch so that could be a check.
I think the coil also gets the same 12 volt from the ignition switch as Injector 1 and 2 fuses, through a splice, so perhaps you've got an issue with the ignition switch or feed if you really do have 9.8 volts. That or the tool or testing is in error.
Originally Posted by dilligaf13
I'm using a Power Probe 4 which specifically has a fuel injector testing function.
2 of the fuel injectors tested at 12.3 and 13.1 ohms so I replaced all the fuel injectors and there's no change. I've never seen a car run less than 12 volts at the fuel injector plug so I still can't see how this car is supposed to run at less than 10 volts to the plugs. I took some of the gas that I pumped out confirming fuel pressure to the rail and it burned in the old fire pit pretty well...
I've replaced the distributor/ICM, coil, ECT, and fuel injectors. I'll try to change the plugs and wires tomorrow but I find it highly unlikely that a few months of sitting caused the plugs to just stop working.... Other than the plugs what else is left besides the ECM on these cars (and is it the ECM, prom, or both)?
GM's service manual says injectors should be 10 ohm minimum and no more than 1 ohm difference between them all. I've seen other notes that it should be closer to 15 ohm.
No, you should have battery voltage (12 volt) to the injectors with key on. The ECM provides the ground that turns the injectors on and off.
Check the voltage on Injector 1 and Injector 2 fuses inside the car. You should have battery voltage (12 volt) there. It gets its feed from the ignition switch. If you got 12 volt at the fuses but less than that at the injector harness, then maybe you've got a wiring issue. However, Injector 1 and Injector 2 fuse feed one bank, individually, so the odds of both circuits have an issue are in question. However, they both share the same supply from the ignition switch so that could be a check.
I think the coil also gets the same 12 volt from the ignition switch as Injector 1 and 2 fuses, through a splice, so perhaps you've got an issue with the ignition switch or feed if you really do have 9.8 volts. That or the tool or testing is in error.
Injector 1 and 2 fuses test at 12V. I tested the wiring at the ignition switch and all the wiring at the switch tested 12V except the yellow ignition wire. The yellow starter wire tested at 10V. Does this wire power anything other than the starter because best I can tell, on the wiring diagram I have, is that it goes to the starter relay?
"The following wires will be on the steering column from the ign switch: CONSTANT 12 VOLTS- Red IGNITION 12 VOLTS- Pink STARTER----------- Yellow ACCESSORY--------- Brown IGNITION #2------- Orange"
Silly me, I thought I'd just replace the ignition switch to play it safe and it's usually an easy job so why not... I've got to say, every time I think this car couldn't have been built and designed worse it apparently takes it as a challenge because in 30 years of working on cars I've never seen a worse designed system than this ignition switch. And because this car just likes f$%^ing with me now, the ignition switch fixed nothing. New ignition switch still shows 10V at the yellow wire.
Last edited by dilligaf13; 10-02-2023 at 01:43 PM.
Are you back probing the injector harness? What is the fuel pressure? Have you checked the spark plugs? I suppose another quick test would be to disconnect the ECM. It's under the passenger's side dash. Then retest the injector harness for 12 volt. I don't think it should change if you got 12 volt on the fuse side. It suggests to me a wiring issue from the fuse panel to the injector harness for the voltage loss/drop unless, again, something is wrong with the testing.
Fuel pressure is 35 psi. I had the fun of replacing the fuel pump right after I bought the car.... Engineers should be absolutely ashamed of themselves at how lazy they were in this design.
I unplugged the ECM and fuel injector plug shows 12V at run and nothing at start up. Probed the injector wires at the ECM and they're showing 12V on run and 9.8V on start. I'm looking for a wiring diagram that shows where the injector wiring running to/from the fuse box goes.
I planned to replace the plugs and wires. They both look fine but obviously not new. Plugs aren't overly wet when I pulled them to check and not all gunked up
I'm not sure if it's related but I found this plug behind the distributor. It comes off the main wire bundle that runs across the firewall down by the trans (for a reference, the distributor and ICM is on the bottom right of that picture and the firewall is on the left). Found that it is supposed to plug in under the coil but it made no change. I found this plug behind the distributor. It comes off the main wire bundle that runs across the firewall down by the trans. Any idea what it goes to?
Last edited by dilligaf13; 10-02-2023 at 07:05 PM.
Looks like a 2-pin Weatherpak. Kinda hard to tell much more about it without seeing the wire colors.
If the wires are pink/black ("gauges"... basically, low-pwr switched ign) and blk/wht (gnd) it's the infamous "mystery connector". Best guess is, it's where the factory plugged in power, to test the ECM and all the other goodies on that circuit at the plant it was made at, before it was all installed in a car at the vehicle assy plant.
That ign sw is basically the same thing that GM has been using since the 60s. Not that that makes it "good" or whatever, just, ... that's just The Way It Is.
JT is right about the injectors, they're usually maybe 15.5 - 16.3 ohms or thereabouts.
Not making sense of this. Where exactly are you testing at the fuel injector harness?
If you disconnect the ECM and disconnect one fuel injector connector (leave the rest), then check for voltage on the injector harness, you should see positive 12 volts on both sides of the fuel injector connector you disconnected because of the way the injectors are connected in parallel and the missing ground. You should not see any ground there because the ECM grounds the circuit to enable them. The ECM can't ground if it's disconnected. And the ECM doesn't ground until it's trying to activate the injectors (during engine cranking or engine running).
If you really have nothing during key start, as you say, then that's another issue. The injectors can't work if it's missing it's power source during engine crank.
One issue to keep in mind with the power probe, or any digital meter, is that it can easily give you a false reading or "ghost" reading because it cannot properly load a circuit. The power probe is a good tool, with many functions, but it can easily mislead.
Originally Posted by dilligaf13
Fuel pressure is 35 psi. I had the fun of replacing the fuel pump right after I bought the car.... Engineers should be absolutely ashamed of themselves at how lazy they were in this design.
I unplugged the ECM and fuel injector plug shows 12V at run and nothing at start up. Probed the injector wires at the ECM and they're showing 12V on run and 9.8V on start. I'm looking for a wiring diagram that shows where the injector wiring running to/from the fuse box goes.
I planned to replace the plugs and wires. They both look fine but obviously not new. Plugs aren't overly wet when I pulled them to check and not all gunked up
I'm not sure if it's related but I found this plug behind the distributor. It comes off the main wire bundle that runs across the firewall down by the trans (for a reference, the distributor and ICM is on the bottom right of that picture and the firewall is on the left). Found that it is supposed to plug in under the coil but it made no change. I found this plug behind the distributor. It comes off the main wire bundle that runs across the firewall down by the trans. Any idea what it goes to?
Looks like a 2-pin Weatherpak. Kinda hard to tell much more about it without seeing the wire colors.
If the wires are pink/black ("gauges"... basically, low-pwr switched ign) and blk/wht (gnd) it's the infamous "mystery connector". Best guess is, it's where the factory plugged in power, to test the ECM and all the other goodies on that circuit at the plant it was made at, before it was all installed in a car at the vehicle assy plant.
That's not C121, is it? It sort of looks like it from the book. The book makes C121 look like an extension for the Intake Manifold Temp Sensor that plugs in near the distributor. I don't recall that. But I also don't recall any mystery connector. It looks like it may not have been connected for a while, though. And the Intake Manifold Temp Sensor doesn't need or use any thick wire or connectors, either.
I'm guessing it goes to a temp sensor because it has 2 metal probe like tabs inside the rubber gromet.
I misspoke when I said the fuel injector plugs showed nothing when I pulled the ECM. The injector plugs are at 12V on run and drop to 10V at start. I back tested the fuel injector wiring in the engine bay at the firewall, at the ECM, at the fuse box all the way back the battery and it's 12V on run and 10V on start. What's the normal voltage drop on these at startup?
I'm reading conflicting information about replacing the ECM and PROM. Mines a 89 Firebird GTA w/ 5.7L TPI so if I'm understanding it correctly, the ECM is not vehicle specific. As I understand it this vehicle has a specifically programmed MEMCAL, PROM and CALPAK? Where is the best place to order these? Thanks
K?
I'm confused by this thread for the following reasons:
1. If the starter cranks the engine, which it does, then it's not VATS.
2. If the injectors have a pulse, which the OP said they do in post #1, it's not VATS, or fuses or ICM.
3. If it has spark, it's not the ICM, Coil, or anything else in the ignition system
4. If it runs on ether, which the OP said it did in post #1, then it's not the ignition system.
5. If it has fuel pressure while cranking, it's got sufficient fuel delivery.
So what's the problem?
after a 6 month crapshow I got the car back from them not running
I think it has clogged/stuck injectors. It has spark, runs on ether, OP says. It has fuel pressure, inj pulse, what's left? Injectors. I'd pull the fuel rail/inj assy, leaving it hooked up to feed/return lines and harness, have someone crank the engine and watch for injectors firing...or not. Have a fire extinguisher close by. I'd bet several or all are stuck/plugged from sitting. But that's the test that I would perform. Pull the fuel rail.
I'm reading conflicting information about replacing the ECM and PROM. Mines a 89 Firebird GTA w/ 5.7L TPI so if I'm understanding it correctly, the ECM is not vehicle specific. As I understand it this vehicle has a specifically programmed MEMCAL, PROM and CALPAK? Where is the best place to order these? Thanks
K?
how did the spark plugs look ? What kv was the coil able to produce for spark ?
if around 40 that’s not your issue. The 1227165 ecm was used on corvette and f body the memcal is the difference and they rarely go bad. You have spark and injector pulse the ecm doesn’t sound like it’s the no start cause. And possibly stuck injectors as mentioned.
At this this point I’ve replaced the injectors, distributor/ICM, coil, spark plugs, plug wires, ignition switch, and jumped the VATS at the pig tail. Only thing I’m aware of left in the starting circuit on these cars is the ECM/PROM (other than something internal like slipping timing chain or failure at the cam’s distributor drive).
IF IT'S CRANKING, IT'S NOT VATS. If you have injector pulse, it's not VATS. Don't waste more time on VATS.
Back to basics. Why isn't it starting on ether now? Re check spark. You probably don't have a way to check Coil voltage output, do you? I don't. Most people don't. What you need to determine is if you have "enough spark", to jump the gap inside the cylinder, while under compression. Take another spark plug from something, anything...your lawn mower, whatever, put it in the boot that runs to the distributor, from the coil. Hold the body of the spark plug to the center terminal of the dist cap (where your coil wire should plug in), crank the engine. If it jumps the gap on your test plug, then it has to be jumping the gap(s) in the cylinders to get to ground.
I agree that the ECM doesn't seem likely. If you got spark, compression, and fuel....the thing should fire.
Note that you can get "a spark" that can jump the gap, in free air; but be too weeeeek to jump the gap at 200 psi.
The spark needs to be a BIG FAT PURPLE kind of a deal that snaps and pops. Not a little weeeeenie orange or blue or white one that barely even makes a tick noise.
I'd suggest leaving the ECM, VATS, and all the rest of that, ALONE. The more you just dink around with, the greater the chances of messing up something that there's nothing wrong with, and you'll just have to figure out and fix later.
I'm confused by this thread for the following reasons:
1. If the starter cranks the engine, which it does, then it's not VATS.
2. If the injectors have a pulse, which the OP said they do in post #1, it's not VATS, or fuses or ICM.
3. If it has spark, it's not the ICM, Coil, or anything else in the ignition system
4. If it runs on ether, which the OP said it did in post #1, then it's not the ignition system.
5. If it has fuel pressure while cranking, it's got sufficient fuel delivery.
So what's the problem?
I think it has clogged/stuck injectors. It has spark, runs on ether, OP says. It has fuel pressure, inj pulse, what's left? Injectors. I'd pull the fuel rail/inj assy, leaving it hooked up to feed/return lines and harness, have someone crank the engine and watch for injectors firing...or not. Have a fire extinguisher close by. I'd bet several or all are stuck/plugged from sitting. But that's the test that I would perform. Pull the fuel rail.
I was too. But if you followed through the entire thread, you will see how it started as one problem and then another. First OP thought it was a VATs problems so they bypassed it. How? Unknown. That's where we started.
The OP stated it started on starting fluid. Then shortly after, it changed to OP stating it no longer started on starting fluid. So that changed from fuel to ignition. Or as I stated, possibly more than one issue.
Also, OP stated less than 10 volts to the injectors with another stating 0 volts. That's why we started checking fuses and circuit. The injectors will operate on 9 volts, but this is a power probe and it's digital. Was it ghost voltage? Further, a noid light takes so little power to fire, compared to injectors or loaded circuit, that it was worth reviewing. Especially given no progress.
Injectors were suspect and stated as such long ago. OP stated they have already been replaced, at some point during this thread.
I, too, wouldn't mess with the ECM unless there was some testing done that damaged it. OP has been using a power probe and testing a lot. Nothing against the OP, as he's trying to fix the car and there's clearly an issue. However, one small mistake with the testing, or the power probe, and the ECM (or other) will be damaged. You just have to hit one button on the power probe to send power to a circuit that wasn't designed for a full 12 volt to cause some big problems.
Copy all that, and I hear you. Hard to help folks when things are seemingly all over the place. It's like helping my Mom w/her car problems from Utah, over the phone to Maine. She's also, all over the place.
"There's no spark".
Did you try switching to Magneto?
"Yes!...wait...no. Well it doesn't make a difference."
It should, it's two entirely separate ignition systems. It had no spark on either, you're saying?
"Yep! No spark at all."
That doesn't make any sense.
"Well....we think that the choke was sticking".
Really. The choke.... Help me, help you. Brutal.
Originally Posted by sofakingdom
Note that you can get "a spark" that can jump the gap, in free air; but be too weeeeek to jump the gap at 200 psi.
Hence, this test:
Originally Posted by Tom 400 CFI
Take another spark plug from something, anything...your lawn mower, whatever, put it in the boot that runs to the distributor, from the coil. Hold the body of the spark plug to the center terminal of the dist cap (where your coil wire should plug in), crank the engine. If it jumps the gap on your test plug, then it has to be jumping the gap(s) in the cylinders to get to ground.
Last edited by Tom 400 CFI; 10-04-2023 at 03:16 PM.
So I “apologize if my post has seemed sporadic”. With work and family I’m lucky if I can dedicate an hour to this project (that I hate) each day. I’ve vacillated between the fuel and spark because the evidence presented has led me in different directions. This has been an devolving project that started as a runner and has gotten worse with time. When I started I got confirmed spark at the plugs (and no, I like 99% of people I don’t don’t have the ability to test voltage on spark plugs other than an noid idiot light and they confirmed power to the plugs) and so I moved to fuel issues. Problematic Ohms on fuel injectors so I replaced them. Fuel is confirmed to the rails, new Accel fuel injectors installed and confirmed 40psi of fuel pressure. I ran the the Pulse Pro 4 and the data to the fuel injectors hasn’t changed. At this point I’m limited on available options that could be causing the no start. Slipping time chain (at this point I’m pulling the POS underperforming/problematic engine and dropping in an crate engine), some bizarre 1 in a million type issue, ECM/PROM (they do effect fuel injector timing, correct???) or some other internal mechanical ****$how (in which case at this point I’m pulling the POS underperforming/problematic engine and dropping in an crate engine). Listen, I know you guys love this car and I get it (my wife loves this model car and I’ve been been working on cars for 30 years and understand emotional attachment to “boat anchors”, I don’t love this car for a long list of shortcomings) but I’m just looking at this thing from a scientific standpoint and this car has pointed in different directions based on the day so sorry if it’s not cut and dry. Trust me, I’d love it if it was more than anyone one this site….
Last edited by dilligaf13; 10-04-2023 at 05:44 PM.
If you were looking at the car scientifically, you'd already have a datalog to analyze. If it isn't popping on starting fluid, it's either spark, timing, or compression. Two of those roads lead toward the distributor.
09-27-2023, 08:29 PM
Hence, this test: