Keoman

iTrader: (3)

I have a little dilema as of right now. Hooked everything up this morning but I cannot for the life of me get the car to start. First we set the timing all over the place, from like 6*-12* advanced then back to 0*...nothing. Checked for spark, plenty. Checked the plug wire configuration and routing, all perfect. When key is turned, fuel pump primes as normal and when the release on the fuel rail is depressed, gas shoots out like normal. When I took the spark plug out, odd thing is that the plug is completly dry. Doesnt smell of gas at all. Im not sure the injectors are firing at all. I read somewhere that they fire all 4 on either side at a time so the order isn't nessisarily important. Is this true? Another observation I made was that when i turn the key on, the service engine light no longer lights up at all.

Some side notes:
Everything went back completly stock. Had valve guides replaced and valves ground as they were in fair condition. I removed the AIR system completly from the engine. Replaced head gaskets, IM gaskets, Head Bolts. We are talking about a 350 TPI here...
Any advice is appreciated.
Keo

travis401

iTrader: (1)

sounds like the injectors just arent firing. try starting it with some ether and see what happens.

Keoman

iTrader: (3)

Just an update.
I went out and checked the Voltages on the injectors. All 8 have 12.8V on each lead and read from 2.8-3.0 ohms when key is on.

Still No SES light... so i tried to pull it up manually connecting pins 5 & 6 which yeilded unusual results. Every time the circuit is closed between the pins, the fans turn on. When the connector is pulled, they turn off. Can anyone explain this?

One more observation. The IAC motor does absolutly nothing when the key is turned. IIRC, it should extend to max length when the ignition is turned on.

I have checked all the fuses under the dash, including the drop down flasher box. All seem to be fine.

Current issues:
1) Car will not fire at all. I know I am getting spark and the engine is timed at 8* advanced as of right now.
2) No SES light.

Keoman

iTrader: (3)

and of course I had the timing Flipped 180*
Thanks for the ether idea. Started back firing like a **** dude...
SES light magically started to come back on and flash like mad while timing the thing again.

sofakingdom

iTrader: (1)

Glad you got it...

There are 2 instances of TDC for each cyl, during each engine cycle; 1 is firing, the other is the changeover from the end of the exh stroke and beginning of the int stroke. Always best to find the compression instance of #1 TDC before dropping the dist in. Which incidentally, is when BOTH timing sprocket dots are at 12:00; when they're "dot to dot", like is easiest to assemble them, the engine is at #6 firing.

travis401

iTrader: (1)

ha, i never new that about the timing dots on the timing gears. i always installed them dot to dot, then rotated the engine till #1 was on the compression stroke then got it as close to TDC as possible then dropped in the dizzy. (all of that was done with the heads on of course)

sofakingdom

iTrader: (1)

Right: "dot to dot" is exactly 1 crank rotation, which is ½ cam rotation, which is ½ of one engine cycle, away from #1 firing. It's #6 firing, and #1 exh-int stroke changeover.

Look at the GM firing order sometime, and let your mind wander over what you see. 1-8-4-3-6-5-7-2. Cyls that are 4 cyls apart in the order are exactly 180° "out of phase"; they are together at all points in piston motion, but are ½ engine cycle apart. This leads to all sorts of uselful insights. Valve adjustment, for instance; if, say, #6 intake is at peak opening, then #1 intake is at "peak closing" and is PERFECTLY PERFECT for adjustment at that point. No doubt the creative mind can come up with all sorts of other useful observations of that sort.

Keoman

iTrader: (3)

Well as of now, the engine starts but runs like CRAP..

1) What I have done:
I rebuilt the top end. Complete Gasket kit, Heads have new guides and ground valves, New head bolts, new IM bolt kit. Torqued the Rocker arms down using the guide. 1 revolution past the first sign of preload on the push rod. I installed exhaust manifold gaskets and coicidently now have an exhaust leak... go figure. New plugs and I will get new wires tonight. Cleaned debris off of the points in the cap and end of rotor.

2) Symptoms:
Car runs like ****. Absolutly no idle, backfires, hard to accelerate engine w/ throttle (chokes out and wants to die below 2500 RPMS) I checked the computer for codes and am getting a 12. No refrence pulses to Electronic Control Module (ECM).

3) What I have checked/tried:
I have triple checked the plug wire configuration, both for connection and for crossovers. All seems fine. Replaced IAC motor. (old motor burnt out before rebuild) Timing from 0* to about 24* before (advanced). Checked connections (pulled and reconnected) around distributor.

4) Questions:
Does it matter what order the injector connectors get plugged in? What do the two sensors on the sides of the heads do? There are 4 ground wires, two on the pass and two on the drivers side of the back of the heads, what are they for?

FYI this is a L98 TPI engine.
Any thoughts?

Thanks

sofakingdom

iTrader: (1)

• Re-adjust your valves with the engine running. Back them off, each one, one at a time, until it clatters; tighten it until it quits; go through all 16 AS FAST AS YOU POSSIBLY CAN doing that. Shut the motor off afterwards and add your desired preload. DO NOT try to add the preload with the motor running, you will just kill it and get LOTS more oil everywhere.
• See #1 for why the car runs like s***. Codes are worthless at this point. Code 12 = no reference pulses = the dist is not turning = duh = the engine is not running. This is exactly what you should see, so that's a good thing, tells you the sensors are all plugged in and producing internally consistent readings, so there's nothing SO wrong with them that the engine can't run.
• Since all you have is a code 12, that means the ECM is happy with all of that. It's not "bad", at least, not so bad that the ECM is incapacitated. Leave it alone and take care of #1.
• No. TPI is batch fire.
  
  Driver's side is the temp gauge sending unit, pass side is the fan switch.
  
  Since all you have is a code 12, leave all that alone and see #1.
  They ground things.Connect them to the most convenient bolt hole possible on the engine.

I'm thinking, once you get the rockers set properly, you'll be happy.

Keoman

iTrader: (3)

Sofaking,
Thanks for the input. I'll give that a try ASAP.

Dont get defensive, im not questioning your knoledge about this. It's just, I know I did it exactly how the manual said to. I guess im just wondering why it doesnt work w/ the engine off? What changes?

sofakingdom

iTrader: (1)

The problem with trying to set them with the engine off is, it's real tough to know, unless you've done it a bunch of times, where zero lash really is. It's not that the book method is "wrong", it's that it's too hard to apply accurately enough. The "twist the push rod until you feel resistance" method, in particular, leads to too-tight rockers. Which is most likely what you've got now: some, or maybe even all, of the rockers are too tight, which hangs those valves permanently open.

You could even verify that if you simply back every one off one full turn, start it up, and see if it runs better.

The best way around the uncertainty is, let the engine tell you when they're right... eliminate the guesswork.

Meanwhile, you want to avoid tail-chasing and messing around with stuff that's really probably completely OK like sensors, and concentrate on the single most likely cause that accounts for all the symptoms. Kind of like my signature says. Use that little pearl of wisdom as your guide to troubleshooting.

Sonix

iTrader: (1)

Think you can explain this to me? I've never heard this, I thought you were supposed to add the pre-load when running as well? Why would it kill it?

Keoman

iTrader: (3)

Thanks, makes perfect sence. Let the engine tell you where it's comfortable. Every engine is different so a cover-all method does seem kinda useless.

Here is where I'm at. This morning I pulled the drivers valve cover and adjusted the rockers as you suggested. Backing off every one until it chattered and then tightening it until the chatter went away. Car actually started to run better by the time I reached the rear of the head. I was pleased with the results and we moved onto the other side. Although it was much more difficult on this side because the engine seems to be backfiring on this side, I did my best. Thing is, by the time I got to the end, the car was not running any better than it did when I finished the drivers side. The car has serious backfiring issues. We played with the timing, Nothing.
This morning I was in a hurry before work so I didn't get the wires on. This afternoon I'll do it first thing and go back and adjust the pass side. I am going to take a video and post it on YouTube.
I preloaded the rockers one half turn after eliminating chatter.
Thanks for the advice.
Keo

sofakingdom

iTrader: (1)

Sonix:

Note how, if you add preload while the engine is running, each time you add some, it runs TERRIBLE for a time, as the lifter bleeds down to its new height. It does this because as long ast the lifter is still too tall, the valve is held permanently open. If the motor ALREADY runs terrible, it's entirely possible that it will be unable to keep running and will die.

Simply zero-lashing them while running, then shutting it off and adding the preload with it stopped, lets you run through the valves MUCH faster and with little to no risk of being unable to restart the engine when it dies.

The end result is the same; you still end up at zero lash, plus x amount of preload. It's just that much easier, quicker, and less hassle to do.

Keo, let us know how that works out. I'm sure you found that you had to loosen at least some of them quite a bit, no? That's because it's SO HARD to recognize for certain, using the "twist" method, when you go from "zero" resistance (lash) to "some" resistance (lash is gone). End result being, you get them WAY to tight without realizing it, because you go so far past zero before there seems to be "any" resistance to twisting.

0pyders

iTrader: (3)

What I did was instead of twisting it I was moving the pushrod up and down until there was no more play in it. Wouldn't that work too? I don't know how in the heck you guys do the twisty method with the assembly lube.

Keoman

iTrader: (3)

Here's where I'm at.
PRE-VIDEO:
Installed new plug wires and again... double checked the routing of the wirings and connections w/ distributor.
Backed ALL the rocker nuts off 1/2 turn.
Started the engine and went through one at a time and tried to eliminate the "clack" from each rocker.

VIDEO
http://www.youtube.com/watch?v=iGvg7u8yHjc

POST-VIDEO
Shut down engine. Pondered. Started the engine again. Engine would NOT idle this time no matter the timing. Dad held idle manually while I went around with a stethescope to each rocker and eliminated the "clack" as best I could. Would not idle, continued to backfire, hard to accelerate motor.

I am at a loss.

I just want to state the things I touched while the heads were off. I took out every Lifter and cleaned it with brake cleaner, oiled them and stuck them back in. I did not let them "bathe" in oil for any significant amount of time, i simply drenched them in a tupperware container for a second and installed them. I also cleaned the retaining plates and did the same. I did lifters one at a time so they did not get put back in another hole. Same with the retainers. My buddy had pushrods that were brand new so i measured them (same length) and THOURGHALY inspected the hole diameter and part for equality. I rolled them on a flat surface to check for any bends or offsets of any kind, nothing. I used his instead of mine that had about 1/32" buildup of carbon on them. Was this a mistake?

Observations this time round:
Plenty of oil pressure. Every pushrod is spitting oil out the top. When the bridge connector in Pins 5&6 was pulled while the engine was idling the first time, it died instantly. Engine will not run under half throttle with the pin connnector removed.

Keoman

iTrader: (3)

Ok,
I have been through every possible senario. Checked, double checked and triple checked timing, TDC alignment, injector voltage and ohms, ect ect ect.. same old ****. Backfiring, barely running at half throttle...


Gonna go buy a new Distributor w/ ECM tomorrow and i swear if that doesnt do it, the camaro is going to get set ablaze.

Keoman

iTrader: (3)

Take a look.
Temp sending unit is either broken/bad. No reading on guage.
Fans are on 100% of the time. Fan switch is broken on passenger head.

http://www.youtube.com/watch?v=sas31sYMU5c
Magically started to idle and then just died.

travis401

iTrader: (1)

We had someone on a local forum have his 'bird do the same thing to him. It was a v-6 though. Strange thing was the car would run great as long as he had his data logging cable plugged into the OBD port. I think he replaced the ECM and it stopped, but i dont remember exactly what the cause was.

travis401

iTrader: (1)

http://www.youtube.com/watch?v=0Vbp0gKo-5s

watch the tack gauge and ses light...look familiar?

itsMikey

if the ses light doesnt blink when you turn the ignition on..id check the ECM fuse and/or the ecm itself.

Keoman

iTrader: (3)

All too familar unfortunatly. Replacing the ECM will by my next course of action.

Mikey,
My SES light is flashing fine. I am able to read codes now and everything. Its got to be something else, maybe the ignition control loop is ran on another deal than the SES codes... Im really bad when it comes to ECM's. A "new" one from the JY or whatever will yeild me peace of mind that it is not the ECM causing this.

Everyone talks about a bad ECM ground. Is there a certain point I can look to test ground continuity or is it slightly more ambiguous than that? Maybe a picture? I really dont even know where the thing is located in the car.

Dyno Don

iTrader: (7)

The grounds are located at the back of each head, there should be three on the right side and two on the left. One on the right is a braided wire.

Keoman

iTrader: (3)

Thanks Don,
I have the right wire count however I think I will take them all off and blast them with a little brake cleaner and some sand paper and make sure everything is kosher before getting another ECM. Wish I had more time!

Found this handy link:
https://www.thirdgen.org/ecminterchange

Thanks again guys.

grumpyvette

http://forum.grumpysperformance.com/...tributor#p7286


this should help

Keoman

iTrader: (3)

What would HELP is if my freaking timing cover had a peep hole in it.

Only way the chain could have gotten messed up is if it jumped a tooth while I was trying to start it in the last week.

Keoman

iTrader: (3)

Well, after some very extensive diagnostics and banging my head against the wall last week, I finally broke down and took it to the Dealership. I figured it was a bad ECM so I went to the JY and got another out of a GMC Sanoma (165) and put it in. The car magically started iding and what not however it is still running like ****. Hunts for idle bad between 900 - 2k RPMS and has random losses in power. Dealership said the Sanoma ECM was bad also... Figures... so I bit the bullet and bought a new one from the parts store. Waiting to hear back.
Keo

travis401

iTrader: (1)

I bet that wasnt cheap. Atleast you know it was a bad ecm....hopefully.

Keoman

iTrader: (3)

Not as bad as i thought, I payed 114$ locally because I needed it that day. Online I found them as low as 70$ w/ core return @ Rock Auto.

Car runs splendid now except for the idle problem. Mechanic was able to pull codes form the ECM and it seems to be peachy. Mechanic at the dealership sprayed carb cleaner around the runners and said it jumped the idle up bad. Definatly an intake leak somewhere. I'm gonna go get it today and tear the intake apart and make sure everything is nice and tight. Anyone use silicone on their IM gaskets?

I also have another question. There is some sort of flange with a two prong connector on it bolted under my coil. What is it? What does it do?

Thanks for the help everyone.