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Discussion Starter · #1 ·
This might be a bit lengthy...

Yesterday, washed engine bay, ran engine, dryed down with a towel then drove the car for about 40 miles, had my trunk power feed AGU fuse start to crap out in the Sears parking lot. (power to fuel pump is some power to my sub amp in trunk, all on a individual fused circuit)

The car would start, then when I put it in gear it would die. I replaced the AGU fuse, and got the car running again and drove the 20 or so miles back home.

Then today, I hook up turbo link, and my fuel pressure gauge, FP line of is 41psi, I move it upto 45psi.

A few seconds later, the car stalls. I restart it and it stumbles and stalls. I try again and I keep the throttle down a bit (~1900 rpm) and the engine holds without stalling. I had about a 1/8 tank of gas, so I decide to go for gas.

I get to the station no problem, fill up, and then the engine won't start.. it cranks and cranks... I try starting again and get a gun-shot loud back-fire followed by a slightly more muffled back-fire. I look under the car to make sure the exhaust is still in one peice.. looks ok so far.

I back the fp down 1-2psi, I turn my translator settings down, (from 20* low gear to 18*, 16* in high, 10% fuel at WOT to None, Lean 3" MAF to base for 3.5" (I'm running a 3.5"))

I reset the ecm, try cranking again.. still no start. I check all the fuses (ECM, ECM SOL, FP/INJ), all good.

I get the car towed back home and I print out the diagnostic charts from GNTType.org.

I read 11.01vdc with IGN on at the PNK/BLK on the engine/ecm harness side of the injector connector. No shorts to ground between the engine bay injector connector and the ecm.

All injectors registered in between 15.8-16.0 ohms, no shorts to ground in the Injector fuel rail harness.

ECM terminal B5 to CKT.430 (pin C on the CCCI), no shorts to ground.

I have no spark from the Coil-pack to a plug wire, no spark from a spar plug removed from head and held to ground.

I have fuel pressure at the rail and it holds pressure.

So, after following the test precedures in the flow-charts, I came down to a faulty ECM.

With all that said, do these symtoms concurr with a potentially bad ECM? To note, the crank sensor, cam sensor, coil pack and module (Eckland) were all replaced by the original owner 6 years ago.

Prior to all this, I didn't have any starting problems of this nature.

Any insight is appreciated, thanks,

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Dan Goldstein
1987 Turbo Regal
 

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I doubt it's a bad ecm. To me, it sounds like a bad crank position sensor. After six years, it could have stopped working.
 

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Was the car charging properly before? What does the voltage at the battery read?
 

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Discussion Starter · #4 ·
i had readings of 13.8vdc on average at the battery at idle in park.

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Dan Goldstein
1987 Turbo Regal
 

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Check for things you might have gotten wet.

Coil pack and module.

Crank or cam sensors.
 

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Okay, it has enuf juice but it sounds like you have a high resistance block somewhere on the way to the ecm....pretty common.

I always post Jim Testa's troubleshooting guide tho I doubt anyone ever uses it.


Here it is....from J Testa

OK, to diagnose ANY car, you need to find what you have and dont have. The way *I* usually go about it (which might not be right to some people, but its methodical and consistant so I stick to it.

1) Note the check engine light (if EFI). If its not on, STOP and find out why. Listen to how it cranks. I can pick out compression problems doing this. If you are in tune to your car, you can too. Listen to the starter as each cyl comes up on compression stoke. You'll hear the starter slow down a little at that point. You bight hear deerdeerdeerdeer, where a dead cyl m ight sound like deerdeeeeedeerdeer (great sound effects huh?)

2)Depending how accessible the intake is, I'll shoot 3 or 4 seconds of carb cleaner into the plenum. Either thru the throttle body, or the brake booster vacuum port. If its a lack of fuel problem, the car may start, it may simply kick. If it does either, its time to look to fuel system (usually, although enrighening can bring out a low sec output problem too, so dont take my suggestion of fuel as law)

3) If the car kicked, I'll put a FP gauge on it. If fuel pressure isnt in spec, now you need to see why. Fuel pump, filter, resticted line, bad reg, low batt voltage, bad relay, blown fuse etc. If FP is in spec, its time to hook up a noid light and verify our injectors are getting pulsed. If youre not getting a pulse you will want to hook up a scanner and look for RPM during crank. If you are getting RPM signal, check for spark. If you're getting spark and no fuel, although there is a commanded PW (see below) you probably have a bad ECM. How fast it cranks isnt as important as the fact you get a RPM signal. Next you'll look at Coolant temp to see if it coincides with ambient )if the car is cold), and verify TPS isnt shorted to Vref which will put the car in clear flood and cut off fuel. If these all look OK, you'll want to take a look at commanded PW.

3) If the car didnt kick, I'll yank a plug wire and see if I got spark. If I got no spark, then I'll check also for inj pulse using a noid light. If I have neither its usually due to a dead crank sensor. If I have no spark, but I have injector pulse, its usually a module.
Typically:
No start - no spark, has inj pulse -> Module
No start - has spark no inj pulse -> ECM / cam sensor prob
No start - no spark OR inj pulse - crank sensor or module

Oh, and if the module is dead, I suggest putting a coil pack on it as well as most of the module failure are caused by an overheating or arcing coil.
 

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Discussion Starter · #7 ·
went out this morning, jacked the car up to look at the crank sensor.

the area had oil residue (timing chain cover, oil pan, etc..)... so i sprayed it down with carb cleaner, then cleaned up as much as I could with a rag.

Then I unplugged the crank sensor, cleaned off the connectors with electrical parts cleaner and a small plastic bristle brush, ragged them down, plugged them back in.

Got in the car, tried to start for the first time since yesterday.

I turn the key to the On position, fuel pump primes, I bump it to Start for a few seconds, It cranks-cranks-cranks, and fires, cranks-cranks-cranks, and fires. The fuel pump primes up like it should after every prolonged bump, but its just not firing enough I guess to get the engine running...

I tried pulling the crank sensor plug out again and more thoroughly cleaning it, trying starting again and now it just cranks and cranks with no fire at all.

Maybe the crank sensor is intermittant? aka crapping out?

Next on the list is I'm gonna drop the car down on the jack and check to make sure the reluctor in the cam sensor is properly secured and that its not freespinning.

I am getting oil pressure when I crank it.

I tried shooting the carb spary in for 4-seconds, then starting it, no kick.

As per yesterday I had no spark from the coil tower to a plug wire, or from a coil tower-to-plug wire-to spark plug that I held out of the engine and grounded.

Cam sensor reluctor is on tight and doesn't free-spin.

So I'm presuming that its either the module or crank sensor at this point.

- Just thoroughly cleaned the tower posts, and the spark plug wire terminals that attach. Used 3m coarse fabric, then some emery paper.. then cleaned out each plug connector with carb cleaner, pick and swabs, then dosed them with dielectric.

When starting the car just a few minutes it ago, it cranks, fires, cranks, fires, fires, cranks...

Also measured resistance between the coils:

3,6 = 11.26 ohms
5,2 = 11.13 ohms
1,4 = 10.14 ohms

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Dan Goldstein
1987 Turbo Regal

[This message has been edited by darkfa8 (edited October 28, 2002).]
 

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Discussion Starter · #8 ·
more testing...

i took the coil off the module and put in a bulb to test the module...

With the Key on I get a light on 3-6, no light on 2-5 or 1-4

With Key in Start, I get a dim, slightly pulsing light on 3-6, no light on 2-5 or 1-4

I read 5.6vdc fluctuating, at 3-5, no voltage at 2-5 or 1-4

The module is a TP400 Echlin unit from Napa, installed roughly 6 years ago by the original owner.

The Coil pack has the following markings on its underside:

369062-1
081 93
MM23689
3089

I ordered a new crank sensor ($32.04) and ignition module ($137.35) from Dal this afternoon.. hopefull that will help, or just be a addition to my back up stuff lol

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Dan Goldstein
1987 Turbo Regal
pt54 (.63, with Limit Engineering turbine heat sheild, hd actuator), mease 15-row stretch ic, jj tb/plenum, 009, extender, t+ 3.5" maf, 2800 l/u D5, billetized-rollerized-blue plated-aluminum panned-Toelle-Burkhart-Shertz built trans, mease dp-test pipe, hooker cat-back, among other sorts of bricka-brak
 

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I know that feeling very well. You might as well bite the bullet and just buy a couple more cars so you have all the spares you need for testing.

A Casper's coil tester is great for checking coils and modules...
 

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Just a thought,under the coil pack (not sure of the name right now)clean them off the terminals and coat with dialectric grease and the same with the coil pack harness.Same thing happened to my friends buick .Let us know what you find.

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TE 45a C.A.S front mount,prec 9.5 3200stall 5 disk lockup t.c,75lbs inj,Red A double pumper,hot wire kit,volt booster,3.5mas translator plus 6.0,THDP,212-212 dutt cam,ported heads and intake,double roller chain,T&A valve covers,art carr deep tranny pan,trans done to 700 hp,scan master,direct scan,Eibach pro kit,Bilsteins shocks,polyurethane bushings body mounts and susp.GNX wheels,nice paint and all the gauges=4075lbb with me and big stereo
 
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