Hello all, I'mmm baaaccck ! I picked up this 83 Z28 with the wimpy 305 cross fire motor a couple months ago, shes got 58,000 original miles on it. Ran pretty good but had to go through the car and change out things like all the vac lines and hoses, suspension bushings, shocks, struts and bunch of other things here and there . I decided to change out the rad and put in a new 3 row full aluminum rad and thats where things turned ugly. Got the rad in and started car to get er warmed up and check for leaks, I usually keep a smart batt charger on it and i had clipped the pos and neg clamps the the plastic batt handle, anyway after running the a couple minutes i turned off car and 1/2 hour later tried to restart and car would not start, cranked and then suddenly as if a big load on the alternator occurred it barely would crank at all and then start cranking again a little bit. I admit that i tried to crank the heck out of it too. Then thats when i found that the pos+ clip that i had attached to the batt handle had come off and was touching the inside of the fender. Soooo Yeaaa, probably shorted the system and computer out. I like to throw money at the problem (NOT!), and so far i have replaced the ecm computer with a A1 cardone reman unit, replaced the alternator ( cause when you turn key on volts coming off it dropped to 8.46 v and turning key down to less than 3v), replaced starter solenoid, and ignition control module. Checked all fuses and all are good, tested the ecm fuse and when cranking test light to fuse was pulsing . Car still will not start but does crank a lot better like normal. The only other thing i can think of is that perhaps the Prom chip got fried too, i have a hypertech chip coming that will be here tomorrow and hope that will get er going again. If not what else do i need to check for ?

 

Wow! That is clean! Congrats on the purchase. Looks great.

I don't think anything got fried. You would have lost fuses before that happened. Have you replaced the battery?

 

Also, i do have an alarm system on car dont know if that may be causing it to not start. It does seem to be ok as it is still arming and dis arming ok and alarm goes off if armed when i open the door for example.

 

I havent replaced the battery, its charging ok and i ran a battery tester on it and it came back as a good battery, no dead cells.

 

I'd change that battery, just for good measure. I'm not familiar with the cross fire system. But check fuel pressure.

 

I did swap in a spare battery i have and it didnt make any difference. I believe the fuel pressure is ok but will check that properly. Before swapping parts out when cranking motor a ton of fuel was dumping from the injectors, not regular pulsating, it was like a straight heavy fuel flow dumping down into the throttle bodys. Thats why i had though the computer was fried cause it controls fuel, and spark.

 

Then I would for sure check out that fuel system. Where did you get those super clean coolant and windshield fluid tanks?

 

Hawksmotorsports

 

Heres a pic of the rad install, still gotta figure out what im going to do for a fan shroud. Dont want to hack up the original one to fit. The 82-84 shrouds



are had to find, there are repops but they are like $170 .

 

check the fusible links down by the starter to see if any of those fried during the short event.Ecm only controls the spark advance-you will still get spark with ECM not working-if engine will not fire on fuel poured down TBIs,check that distributor is getting power and if it is and no spark,try another ICM.

 

Ok thanks will do. I did install a new icm yesterday .

 

Question on the fusable link to starter: I take it that that fuse link would be in line one to the "S" post to starter solenoid ? If that link was blown would starter not work/turn at all ?

Is there a list of what gauge the different fusable links are ? Service manual only shows the gauge for link C to ecm as a .5 = 20 awg . But it doesnt say what gauge the links to starter A&B, doesnt look like theres one for the alternator . Theres a fuseable link H to ignition switch no wire gauge on that either.

 

There is no fusible link in the "S" wire.

They are in the Big Red Wires that carry power TO things, including the ignition switch. There is not one in the wire that carries power TO the solenoid (purple wire); only in the ones that carry power FROM the batt cable at the starter, TO other things via the Big Red Wires, such as the ign sw, headlight sw, and so on.

Fusible links are generally 3 or 4 gauges smaller than the wire they protect. Since the Big Red Wires are #10, that means the FL is usually #14. They are color-coded to make it easy to pick the right size without even having to know that. The color you most likely need is "rust"; a sort of brownish-orange shade. You can buy em hanging on cards in the Electrical goodies section of just about any parts store.

 

just have to grab a voltmeter and see what doesn't have voltage then start following back until blown wire or fuse link is found.

 

Ok, dug into things a little today, so this orange wire with this that looks like a connector i take it as being the "C" fusible link to ecm/fuel injection, that tested on both sides with power, so good. Testing for power from the fusible links A&B at the starter, with key on power from there is getting to the +red wire at the 2 pin connector to alternator and to +red to ac/heat blower control and from there that wire goes down to and connects the fusible link H ( which i can not find ) and goes into/for ignition switch and then continues to the fuse block and connects to one of the circuit breaker fuses, tested those 2 and there is power to and through both
, so i believe link B and H is ok. Dunno. Am i missing something ? Car still wont start though . I did find another one of those connector like fusible links over the back pass side of valve cover that is org with black stripe, dunno what that ones for.

 

 

Checked the spark today with the , Cranking motor there is pulsating reddish spark. Shouldnt it be bluish white ?

 

Ok, dizzy working and spark present.Do you get "check engine"light on when ignition switched on?if yes, jumper A&B on the underdash diagnostic plug with a length of wire and switch on the ignition-the CEL should flash a code "12" and then any stored fault codes-if no fault codes,"12" will repeat.If there is no response from the CEL,there is no power to the ECM or something wrong with it or the wiring.

 

Finally got to it this morning. Jumper to A n B port, Flashed code 12 a dozen times before i turned key off. "Code 12No Distributor Pulses" . I changed out the coil and the ICM. I did another check for spark and still got the red sparking . Have i perhaps over looked replacing the ignition pickup also or perhaps still an ecm issue ? I did check the Orange power wires into ecm and its getting power. Also to note, i got the starter changed out this morn and a new battery, car cranks a lot better than before but then after about 5 seconds of cranking it stops and hangs up like it doesnt want to turn at all .

 

there is still a major electrical problem unrelated to the distributor or fuel injection-check the braided copper ground strap bolted to the back of the RH head and connecting to the firewall and (if your car has it-mine does,but might not be stock)the ground from the batt neg. to the body.

 

Checked all that and good.
Put in another new ICM and new cap n rotor yesterday and still no start. Cranking good though. Tested voltage and continuity from the fusible links by starter to the 2 red power wires they feed just before they enter the firewall on drivers side and got good pwr to that point, good power to ignition switch and fuse block.
Just for the heck of it i re installed the old computer and car wouldnt crank at all, it was trying but wouldnt turn. Dunno what the heck else. Gonna have to throw in the towel and pay the big $ to get it towed to a shop, or call mobile mech..
Think im going to order another stock computer from a junk yard and see what happens. Wondering if the cardone reman ecm and or the hypertech chip i got are not working.
Probably flooded the heck out of it too cause as cranking theres a lot of fuel dumping down into the TB,s .

 

Before you go any further, take out a couple plugs and check to see if they are soaked with fuel. If they are, you'll never get it started. Check the plugs first, then pull out your oil dipstick and see if the oil smells like gas. You may have flooded the crap out of it, almost sounds like it hydro-locks cranking...

 

Ok, thanks, will check that when i get time. If fuel in oil would i have to change oil out ? If plugs wet ?

 

All that means is, the engine wasn't turning while you were reading the codes. It is not a "defect". It's supposed to give that code.

The ECM won't cause it to fail to crank, or to crank slow. It's totally unrelated to, and uninvolved in, the starting system. In any case, that's one of the good things about that old 70s POS ECM that came in those; they may be slow and very limited in what they can do, and damn near impossible to reprogram, but they're pretty robust and don't often fail. Like the carb cars, it's almost never The Problem, no matter what The Problem is. Put whichever one back in, and leave it alone. I'd recommend putting the original back in so you don't accidentally introduce a SECOND problem that might be AWHOLEHELLUVALOT HARDER to troubleshoot than a no-start. Maybe even, a runs-like-crap, or a only-runs-sometimes, or any number of other, MUCH harder things to deal with.

The ECM CAN however, cause a no-run problem. It would be exceedingly rare but is at least possible. BUTT: you can simply disconnect the big flat 4-pin electrical connector hanging out of the back of the dist, thereby COMPLETELY taking the ECM out of the run/no-run equation, and pour some gas or spray some starting fluid into the TBs, and it should run for a few seconds. Can't really drive it like that of course, but at least you can get it to run.

A no-start has got to be the EEEEEZYEST kind of thing to troubleshoot. It's really quite simple... the engine needs 3 magic ingredients to run; compression, air/fuel in a reasonable ratio, and spark at the right time. If it cranks but doesn't run, all ya gotta do is, figure out which of the Magic 3 went away.

Compression rarely just "goes away"; but it CAN, specifically if the timing chain has failed. (or more likely, the cam sprocket) If this happens the valves will be open at all the wrong times while the pistons are moving up and down. Simple enough to check for that; just have your assistant crank the car, after charging the battery FULLY, while you watch the distributor rotor. If it turns smoothly and continuously, then the timing set is OK. If it seems to move in a jerky or uneven way, and especially if the engine sounds real strange like compression is going out the exhaust or into the intake, then the timing set is failed.

Air hardly ever "goes away", but fuel of course does. VERY EEEEEEEZY to substitute for: just pour a bit of gasoline down the TBs, then crank it, and see if it will at least HIT. It should in fact RUN for acoupla seconds if you had poured in enough fuel. DO NOT pour fuel in while it's cranking; all sorts of REALLY BAD things happen from doing that, ranging from a "Holley haircut", to exploding gas cans, to setting the car on fire. Pour the gas in, THEN try to start it. If it does run from doing that, then you have spark, and The Problem - there is usually ONLY ONE Problem - is fuel related. If it doesn't, then you have a spark problem.

Be logical, rational, and methodical. Use reason and mental power to THIMK about what you're doing. DO NOT let yourself get dragged into "maybe it's this maybe it's that", loading up the parts cannon and just blasting parts at it, or any of that stupidity. THIMK.

Once you have localized The Problem to which Magic Ingredient is missing, then you can methodically and logically and systematically attack THAT PARTICULAR SYSTEM of the vehicle, with certainty that you're actually working toward The Problem, instead of just mindlessly thrashing around in futility.

 

In addition to Sofa's post, I would unplug the connectors off the top of the injectors before putting any fuel or carb cleaner down the throttle body... at least for his initial test to see if it runs for a second..
check those plugs and oil first though! A bunch of fuel in the oil can lead to an unpleasant explosion if there's enough vapors to light the fuel off.

 

Ok, so i did swap out the new computer n chip and put the orig ecm n chip back in and car would not even turn/crank at all, motor was trying but no. With new ecm while cranking motor i do see a big heavy fuel flow from injectors into throttle body, as i recall from before as with car running fuel flow was light and pulsating.
I just pulled oil dipstick and theres a ton of fuel in oil. The oil is kinda clear cause i had changed out the oil a few weeks ago with 0 miles drivin on car since oil change, i added pic of dipstick and its hard to see but the level is all the way from the full line to that fitting, like a good 5" past full line ! Pulled #1 plug and its soaked .

 

Wow! Drain that stuff out of there! Be careful as it will be flammable!! There's gonna be like 2.5 gallons of liquid there, so have a couple different drain pans handy.

Change the filter as well.

Unplug the injectors, change the plugs and crank it a little bit to get some fresh oil into the bearings. It may pop off and run for a second or two but won't run long without the injectors hooked up.

Once you get this far let's see what the status of everything is..

 

Thanks will do, prob wont be till this weekend. Instead of unplugging injectors i can unplug the fuel pump fuse also ? should be ok . I might put some gas in a spray bottle and spray into tb's as cranking to get er going a bit "hopefully" .

 

I never use gas as a test fluid, too much chance of the bottle igniting in my opinion. I use spray carb cleaner. A couple second burst in each throttle body should be enough to light it off to test.

 

I'm not sure if pulling the pump fuse would kill the power to the pump... You'd have to pull the fuse, then turn the key and listen for the pump to not run..

 

Does anyone like the "Z28 Camaro" on the side of the doors ? I kinda dont like it and might look into getting those removed.

 

Ok, so this morn i changed the oil and unplugged the 2 fuel injectors and cranked motor and sprayed starting fluid into throttle bodys and car runs and starts. Plugged injectors back in and cranking but no start and its still dumping a ton of fuel into TB's . Correct me if im wrong but on these cfi cars when cranking motor over the fuel from the injectors controlled by computer and supposed to be like a light pulsating fuel spray into tb's ?
Other tests i did was i plugged back in the original ecm and chip and car would not even want to crank. Pulled the orig chip from orig ecm and installed the hypertech chip, car cranks but still getting the big fuel dump and no start. Next i put the ai cardone reman ecm back in with the hypertech chip and same result - car cranks but still getting the big fuel dump and no start. Put in the Original chip with the cardone reman and car cranks but still getting the big fuel dump and no start . So i tried all those combinations and no start. I did change out the fusible link to the ecm, tested voltages at the ecm connectors and getting proper voltage . PUt my test light to the ecm fuse and cranked engine and test light has pulsating light when cranking. So problem seems to be getting too much fuel flow when trying to start. would it not still start or try to start over even if its dumping too much fuel ? Perhaps the cardone reman ecm is bad too. I did finally found another stock ecm and chip but it wont be here till Monday, i would think after installing that with same end result its something else, LoL. At least i will have a spare ecm, and these 1226026 cfi ones are hard to find.

 

OK, that's REAL GOOD news. At least you know the timing set hasn't failed and the distributor works. You've narrowed it down to a fueling problem.

While I hate to advise the parts cannon, occasionally it's not a bad way to deal with a situation. Especially when it's something cheeeeeeep and eeeeeezy to swap out.

Sounds almost like the ECM thinks it's -50° or something. Try a coolant temp sensor. Check it carefully first to make sure it's plugged in, the wire isn't broken like right at the connector, etc. Then put the original ECM and original chip back, and try it, since those have nothing whatsoever to do in any manner way shape form or fashion with cranking and any perceived relationship is pure coincidence, and are most likely NOT to introduce new unforeseeable inscrutable problems.

I'm not a fan of the stick-on graphics. Looks like cold leftover yesterday's butt IMO.

 

Be careful you're not flooding out the plugs again. The injectors should lightly pulse at idle. If it's hosing out, there's a control issue. Like Sofa says, the Coolant Temp Sensor tells the ECM what base fuel map to try to start with. It takes a lot more fuel at 20 below, than it does at 50 degrees.

Did we discuss checking all the grounds on the engine? There's a few of them, maybe on the back of the heads, and on the intake. Find them and unbolt them, clean the area they go to, and reattach them tight.

 

The plug to the CTS can be shorted to fool the ECM into 'thinking' the motor is full hot.

a stuck open injector may flow even when the motor is not cranking, provided the fuel system is pressurized.

 

I will check the cts and grounds here shortly, thanks guys

 

This is VERY true, especially with the old "coaxial" sort of CTS connector. In fact if your car has that, it might have been The Problem all along. They're also notorious for not making a good connection.

If your car still has that, you need to change it, REGARDLESS. It is The Dung. Get a new one; make sure it's the one that comes with the pigtail, and that the pigtail is still in the box. Install the new pigtail to the wires with solder and heat shrink tubing, NOT crimp butt splices, or the crappy Scotchlock things it comes with. Part # at AZ is SU102. Look it up: If yours doesn't look like that, REPLACE IT NOW.

If the injectors didn't continue to dump fuel when unplugged, then they're not "bad" in that particular way. (stuck open, or so overwhelmed with crap that they're WEDGED open) However, it's ASTOUNDING how much better a TBI will run with clean injectors, compared to old cruddy ones. They are EXTREMELY EEEEEEEZY and CHEEEEEEEEEEP to "rebuild" yourself. Get yourself a paper & rubber kit for em, take em off, tear em down, and soak em in lacquer thinner for a few hours. Overnight is good. Reassembly and reinstallation is the reverse of removal and disassembly, no adjustments or anything else required; just stick em back on, except maybe, since you have the dual thing, you might have to "sync" the linkage.

 

Ya so i just looked at the cts and the wiring is crusty and bare and it looked like the wires were twisted together a bit. Went to dis connect the connector and it fell apart. Was trying to remove the old sensor and it wont budge, didnt want to over do it for fear of that breaking off in the manifold. Looks to be aluminum manifold , wondering if i can heat that area up a little with a hand torch to try and loosen that sensor up or not a good idea ? I have this other new sensor but its just the single pin one, dunno if perhaps i can make it work, i take it the wht wire would go to that single post and the black the ground and wrap that around the threads of the new sensor just to get it working for now ? Heres that AZ connector:
https://www.autozone.com/engine-mana...archText=SU102
Just wondering on that what wire goes to what ? Original connector has 1 wht and 1 blk wire, the connector on that az one are both blk. Or does it matter with that sender what way makes a difference ?
Found a

Engine Coolant Temperature Sensor Standard TX4 off ebay, ordered that and just deal with it next weekend. Id go to Az to get it but its 20 miles away and they put me on hold forever + i dont feel like driver over there anyway, LoL. What to see if i can get that old one out and get that single pin one to work temporarily .

 

That round connector looks EXACTLY like they always do. Except that in some cars they wrapped it with some kind of tape that has this real gooey glue to it, so in addition to the wires being all crustified like that, they're covered in blank funky goo too. Gotta be a candidate for the stooooopidest connector design EVAH. Its only serious competitor is the one that feeds battery to the blower motor high speed relay, and the one that feeds Accessory to the AC "mode" switch. Don't worry, once you start trying to use the car, you'll be posting about those too.

I wasn't kidding when I said that the CTS might have been your problem all along... if the connector doesn't make good contact, then the ECM thinks you're in Antarctica, and dumps in enough fuel to start it at -70° or something. OTOH when the wires touch, the ECM sees engine temp of like 350°, and puts in almost no fuel at all. One way it's just BEYOND STUPID rich, and fouls plugs and so forth; the other, it runs EQUALLY STUPID lean, and it's gutless, has no power, stumbles, surges, and otherwise acts like it's not getting any fuel. Because it's not.

The ebay one is perfectly fine. Exactly the same thing as the AZ one I linked you to. As long as the pigtail is actually in the box when you get it. Which of course you can't exactly open the box and look, like you can at a physical parts counter.

Gonna have to remove the old sensor. No 2 ways about it. I recommend breaking off all the old plastic part of it with a pair of giant pliers, and using a 6-point socket on it. Maybe spooging it up real good with PB Blaster first. Don't worry, it'll come out; it's brass, doesn't corrode in there like some other metals would. Might break off the water outlet if it's corroded through and got weeeeeek, but if it breaks, it's because you already needed a new one anyway.

Doesn't matter which wire goes to which pin. Some of the new ones, the pigtail has 2 black wires; doesn't matter which one goes to the car's yellow wire and which goes to the car's black.

If the "single pin" one you are talking about is that gauge sending unit in the photo, then no, it will not work.

 

Well gee wiz, got'er going again yeeaaaaaa ! So ya i guess it was the coolant temp sensor was the culprit, who would've thunk it. F me sideways silly seven times ! So, i have 3 computers now, after replacing the temp sensor i put in the other computer i just got off ebay and she fired right up. Swapped the prom chip around from that ecm between the other 2 ecms, and swapped around the hypertech chip and put my original chip and ecm back in and all combinations work to fire up the car. The battery and alternator were under warranty so those didnt cost me nuthin to swap out, had to pay for starter/ICM/cap/coil/fusible links ect. .

 

Well it appears that there are now a bunch of the cardone 77-6026 ecm's that popped up on ebay, so if ya need an extra ecm for your cfi car now the time to grab one. The prices are now $138 with a $100 core charge though. they were about in the $70 range a couple months ago with no core.

https://www.ebay.com/sch/i.html?_sop...&ul_noapp=true