hot engine no start
Thread Starter
Intermediate
Joined: Mar 2007
Posts: 27
Likes: 0
From: Parlin New Jersey
hot engine no start
my car is a 1989 coupe with a 6speed manual trans with 70000 miles. ok i changed the plugs, wires, cap, rotor, icm. car started up and ran fine. turned the car off went to start car about 5 mins later and would not start. the car will start when cold but once the car reaches normal operating temp the car wont start. did a fuel pressure test and it was fine so i dont believe i have any leaky injectors. took tb off and cleaned it also pulled iac and made sure there was no carbon buildup. i am at a lost on what to do next. any help will be appreciated. btw the computer shows no codes at all.
Last edited by t00ms; Jun 23, 2008 at 05:13 PM.
Melting Slicks
Joined: Jan 2008
Posts: 2,065
Likes: 1
From: Jasper Texas
I was going to suggest injectors, but you seem to have ruled out that possibility. What does it do when it won't start? If you give it some gas, will it start? Have you checked for the presence of trouble codes?
Oh, and was this occuring before the work you did to the ignition system, or did it start afterwards?
Oh, and was this occuring before the work you did to the ignition system, or did it start afterwards?
Thread Starter
Intermediate
Joined: Mar 2007
Posts: 27
Likes: 0
From: Parlin New Jersey
ther are no trouble codes. the engine just cranks when i try to start. i tried pushing the pedal all the way down and than tried to start but nothing. it happened before i changed everything and it was suggested to me that it was the icm but that doesnt seem to be the problem. i really dont want to be changing everything on the car. i have a fsm and been trying to trouble shoot the problem but everything i try doesnt seem to fix problem. i know it is probably staring me in the face but i just cant see it.
Supporting Vendor
Joined: Mar 2008
Posts: 1,762
Likes: 14
From: Cumming Ga
I was going to suggest injectors, but you seem to have ruled out that possibility. What does it do when it won't start? If you give it some gas, will it start? Have you checked for the presence of trouble codes?
Oh, and was this occuring before the work you did to the ignition system, or did it start afterwards?
Oh, and was this occuring before the work you did to the ignition system, or did it start afterwards?
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Check for spark, hot ign modules and/or hot spark coils fail when hot when they get old or put out a weak spark. You should easily see a 1/2 inch snappy spark at the plug wire. Put a noid light (available at parts stores), or a low power 12v lamp like a 194 side marker lamp across an unplugged injector wire and crank, you should see the lamp pulse.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
Check for spark, hot ign modules and/or hot spark coils fail when hot when they get old or put out a weak spark. You should easily see a 1/2 inch snappy spark at the plug wire. Put a noid light (available at parts stores), or a low power 12v lamp like a 194 side marker lamp across an unplugged injector wire and crank, you should see the lamp pulse.
Thread Starter
Intermediate
Joined: Mar 2007
Posts: 27
Likes: 0
From: Parlin New Jersey
ok i ohmed tested the injectors they are as follows, cold readings are 1,3,5 read 16.1, 7 reads 15.8, 8 & 6 reads 12.2, 4 reads 14.7 and 2 reads 16.4
the hot readings, engine temp approx 200 they are as follows 8,4 & 3 read 8.1, 6 reads 7.5, 2 reads 8.9, 1 reads 14.1, 5 reads 16.7 and 7 reads 6.5. I also did a fuel pressure test and it read 41.5psi and held after about 30 mins it dropped down to about 30 psi .
I also put a light on the injector connections and they all pulsed as the car cranked.
the hot readings, engine temp approx 200 they are as follows 8,4 & 3 read 8.1, 6 reads 7.5, 2 reads 8.9, 1 reads 14.1, 5 reads 16.7 and 7 reads 6.5. I also did a fuel pressure test and it read 41.5psi and held after about 30 mins it dropped down to about 30 psi .
I also put a light on the injector connections and they all pulsed as the car cranked.
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Supporting Vendor
Joined: Mar 2008
Posts: 1,762
Likes: 14
From: Cumming Ga
ok i ohmed tested the injectors they are as follows, cold readings are 1,3,5 read 16.1, 7 reads 15.8, 8 & 6 reads 12.2, 4 reads 14.7 and 2 reads 16.4
the hot readings, engine temp approx 200 they are as follows 8,4 & 3 read 8.1, 6 reads 7.5, 2 reads 8.9, 1 reads 14.1, 5 reads 16.7 and 7 reads 6.5. I also did a fuel pressure test and it read 41.5psi and held after about 30 mins it dropped down to about 30 psi .
I also put a light on the injector connections and they all pulsed as the car cranked.
the hot readings, engine temp approx 200 they are as follows 8,4 & 3 read 8.1, 6 reads 7.5, 2 reads 8.9, 1 reads 14.1, 5 reads 16.7 and 7 reads 6.5. I also did a fuel pressure test and it read 41.5psi and held after about 30 mins it dropped down to about 30 psi .
I also put a light on the injector connections and they all pulsed as the car cranked.
Instructor
Joined: May 2007
Posts: 109
Likes: 0
From: Ostersund (Sweden)
The Injectors.. are they changing resistance when they are hot?
My car is weak as a 100 hp car after some hard driving. Can't rev it to more than 3500rpms. I checked the injectors when it was cold and they all were from 15.0 to 15.3 ohms.
Supporting Vendor
Joined: Mar 2008
Posts: 1,762
Likes: 14
From: Cumming Ga
Burning Brakes
Joined: Nov 2007
Posts: 1,213
Likes: 2
From: Cincinnati oh
my car is a 1989 coupe with a 6speed manual trans with 70000 miles. ok i changed the plugs, wires, cap, rotor, icm. car started up and ran fine. turned the car off went to start car about 5 mins later and would not start. the car will start when cold but once the car reaches normal operating temp the car wont start. did a fuel pressure test and it was fine so i dont believe i have any leaky injectors. took tb off and cleaned it also pulled iac and made sure there was no carbon buildup. i am at a lost on what to do next. any help will be appreciated. btw the computer shows no codes at all.
My did the exact same thing! if the fuels drops off quick afte you shut it off, it is the fuel pump Mine did the exact same thing its a 50.00 fix and easy to do.
Melting Slicks
Joined: Feb 2005
Posts: 2,135
Likes: 0
From: Sebastian Florida
St. Jude Donor '06
Was the car running fine before the tuneup?
I find it hard to believe that FI's could be good before the tuneup and bad after. Did you use dialectric grease on the ICM?
I find it hard to believe that FI's could be good before the tuneup and bad after. Did you use dialectric grease on the ICM?
Last edited by Randy93; Jun 16, 2008 at 11:46 AM.
Intermediate
Joined: Jul 2005
Posts: 38
Likes: 0
From: PHILLY PA
tooms,,(1990 vert) ,i bought 8 injectors from FIC. 1-770-888-1662,, ask for Jon,,,will help you out,,,great customer service,,,
Last edited by blck90vette; Jun 16, 2008 at 07:10 PM. Reason: spelling
Thread Starter
Intermediate
Joined: Mar 2007
Posts: 27
Likes: 0
From: Parlin New Jersey
I just ordered the injectors from FIC. Spoke with Jon, very nice guy and really takes the time to explain everything to you. Hopefully when I install these injectors problem is solved to which I think it will be. Will update post after injectors are installed. Thanks to everybody for the help and info, I really appreciate it.
Thread Starter
Intermediate
Joined: Mar 2007
Posts: 27
Likes: 0
From: Parlin New Jersey
Just to update everybody on my car, I bought injectors from Jon at FIC and was able to put them in yesterday after several hours (haha) and now the car runs better than ever. No more problem starting it up after its hot. I would like to thank everybody on here especially Jon for all their help. I dont think people really realize what kind of information is on this site. There are so many people here that are willing to help if we just ask for it, and anybody that is going to check their injectors remember to ohm them cold and than ohm them hot cause you might be surprised.
