Multiple Problems.. new info.. 85
Pro
Joined: May 2006
Posts: 637
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Didn´t see anyone mention a possible coil failure.
I might be way off but a simple thing to check is the small wires that connect to the coil on the left side of the distributor.
You didn´t reverse them by mistake?
You have to firmly seat them or at least check them so they make good contact.
Or the coil itself might be fried. Don´t know if you replaced it or not...
Just a thought...
I might be way off but a simple thing to check is the small wires that connect to the coil on the left side of the distributor.
You didn´t reverse them by mistake?
You have to firmly seat them or at least check them so they make good contact.
Or the coil itself might be fried. Don´t know if you replaced it or not...
Just a thought...
Last edited by vette079; Jun 23, 2008 at 10:49 AM.
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
I replaced the ECM ...the original unit only had one PROM chip in it but two slots....The car didnt run any better so I took it to the GM dealer to have it scanned...they said the computer tells them MISSING EPROM and will not continue....they checked and GM does not make those chips any more....Does anyone know where I can find one? I checked with Hypertech and they say their chip is only replacing the larger of the two...Thats not the one I need.... Please help.....
When you're sure the timing is right at #1, check again the wires sequence. REMEMBER, the cap is upside down when you look inside.
When you're sure of timing and wires sequence, the motor should start.
vette079 Didn´t see anyone mention a possible coil failure.
If it does not start, air is blocked (air filter; not likely, but check anyway), or fuel is wrong. Test the fuel pressure.
Post back what you get done. Each step has to be followed accurately to rule stuff out!!!
Last edited by schrade; Jun 23, 2008 at 12:06 PM.
Thread Starter
Intermediate
Joined: Sep 2007
Posts: 43
Likes: 0
From: Scottsboro AL
Since you got the comp guage, you can double check that the timing is correct (good enough to start the motor).
When you're sure the timing is right at #1, check again the wires sequence. REMEMBER, the cap is upside down when you look inside.
When you're sure of timing and wires sequence, the motor should start. Are you still getting spark, like you said in post one update?
If it does not start, air is blocked (air filter; not likely, but check anyway), or fuel is wrong. Test the fuel pressure.
Post back what you get done. Each step has to be followed accurately to rule stuff out!!!
When you're sure the timing is right at #1, check again the wires sequence. REMEMBER, the cap is upside down when you look inside.
When you're sure of timing and wires sequence, the motor should start. Are you still getting spark, like you said in post one update?
If it does not start, air is blocked (air filter; not likely, but check anyway), or fuel is wrong. Test the fuel pressure.
Post back what you get done. Each step has to be followed accurately to rule stuff out!!!
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
Drifting
Joined: Nov 2005
Posts: 1,361
Likes: 0
From: Downriver Mi.
This is what I would do,take valve covers off and re adjust the lifters,next i would re drop the dizzy.then go from there,If your not exp. then take it to someone that is or find someone the knows their stuff to help you,If the car ran fine before head gaskets I would look at stuff touched buy your backyard wrench.you may have a lifter or 2 too tight(collapsed) or the dizzy off a tooth thats my bet.The car runs fine you throw a belt and it overheats blowing a head gasket,why would you mess with the e-prom??You better find a real wrench or you better have deep pockets.
Last edited by MR NICE; Jun 24, 2008 at 07:10 AM.
Safety Car
Joined: Oct 2007
Posts: 3,816
Likes: 0
From: :45 minutes from everywhere / E-I-E-I-O
Timing is off.
I don't understand how, because you checked that cylinder 1 is on, or close, and that alone would NOT allow enough timing deviation to ignite gas in the exhaust...
UNLESS, some wires are crossed - but you double checked that.
OR, it is suckin' some SERIOUS air, and gas ain't vaporizin' enough, and it is goin' through the cylinders partially UNburned, and it is there lightin' up the exhaust.
Have you checked spark at each plug? Connections at each end of all 8 wires? If one or two ain't firin', some fuel will get into the exhaust this way also, and there light up the pipes...
I don't understand how, because you checked that cylinder 1 is on, or close, and that alone would NOT allow enough timing deviation to ignite gas in the exhaust...
UNLESS, some wires are crossed - but you double checked that.
OR, it is suckin' some SERIOUS air, and gas ain't vaporizin' enough, and it is goin' through the cylinders partially UNburned, and it is there lightin' up the exhaust.
Have you checked spark at each plug? Connections at each end of all 8 wires? If one or two ain't firin', some fuel will get into the exhaust this way also, and there light up the pipes...
Last edited by schrade; Jun 24, 2008 at 02:40 AM.
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Thread Starter
Intermediate
Joined: Sep 2007
Posts: 43
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From: Scottsboro AL
Its been at the local dealership for about 3 weeks...They said I needed the calpak....so I bought one..they said that cleared all the codes in the computer, they then replaced the spark plugs for the 3rd time saying the rich conditions were burning them....then they replaced the MAF. Shes running like a dream....with one exception....it does not want to go when its cold...after the engine runs a few minutes she goes back to her old self ....any ideas? Dealer said it might be injectors needing replaced....I dont think its that severe...what do you guys think??
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
Check and double check your TPS, I just finished a 6 month battle with my '85 not wanting to stay running when cold but once it got to 130* it would idle and run like a champ. After checking my min. air idle about a dozen times I was giving it another check when I noticed the voltage going all over on the TPS. This had never happened before during all the checks. I replaced the TPS and the problem was gone.
Le Mans Master
Joined: May 2004
Posts: 5,866
Likes: 60
From: Hellinois
Finalist 2020 C4 of the Year - Modified
Bump the tps up to .54, that is the minimum setting. IF it gets better but doesn't completely cure it them bump it up to .56. You can go as high as .62 if memory serves me but keep in mind that a higher tps setting will also increase idle speed slightly.
Last edited by Midnight 85; Jul 18, 2008 at 01:50 PM.
