1990 will not start
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From: Houma, LA.
1990 will not start
My car is still in the process of becoming road legal due to the fact that it is awaiting a paint job and is partially disassembled (no front or rear lights). I start it every now and again just to keep things in working order. I tried to start it last week but the battery was dead. I hooked up the battery charger and put it in boost mode but still could not get enough juice to start. I let it charge for and hour or so in medium charge mode and it started fine. I then shut it off, disconnected the battery and let it trickle charge for a few hours. I now can't get it to start. It sounds like it wants to start but just will not. I have 34lbs of fuel pressure at the rails as seen by my fuel pressure gauge that I have installed. I smell fuel from the exhaust. I have not yet check for fire at the plugs. It is acting very similar to the time that my LH went bad and had to be rebuilt a few years ago. I'm gonna be working on it tomorrow if you guys have suggestions of things to check?
Three Wheelin'
Joined: Feb 2004
Posts: 1,748
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From: St. Augustine, FL
My money is on you fried your LH trying to "JUMP" your car using a battery tender in boost mode. You're in good company because I'm fairly sure I did the same thing to MY 1990 
LH is a prime replacement unless you want to do like me and replace EVERYTHING else first. Read more here
https://rennlist.com/forums/928-foru...-no-start.html
LH is a prime replacement unless you want to do like me and replace EVERYTHING else first. Read more here
https://rennlist.com/forums/928-foru...-no-start.html
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Race Car
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From: Houma, LA.
Here is the latest. Following JDSPorsche trouble shooting list.
1. Car has fuel
2. No clicking noise when key is turn on without starting
3. I have strong spark on both cylinder banks
4. The fuel pump comes on then shuts off at 36lbs according to the fuel gauge that I have mounted on the injection rail (I know its low but I know why its like that and it's been like that when it ran)
5. this step of the trouble shooting guide does not apply since the fuel pump relay is good.
6. Kick down relay is the correct one (not a #53)
7. The spark plugs were wet with fuel, I pulled the fuel pump relay ( no fuel to rails confirmed by meter) pressed the pedal to the floor and cranked the engine. It stumbled once or twice then just rolled with no attempt to run. Replaced the fuel pump relay and had basically the same symptom (engine stumbles but no start).
So trying to reason out why I have fuel, spark but no start........ The LH is dumping too much fuel causing the cylinders to flood and since there is not proper atomization of the air fuel mixture it will not sustain running condition. Does that sound about right? Anything else to try? check?
1. Car has fuel
2. No clicking noise when key is turn on without starting
3. I have strong spark on both cylinder banks
4. The fuel pump comes on then shuts off at 36lbs according to the fuel gauge that I have mounted on the injection rail (I know its low but I know why its like that and it's been like that when it ran)
5. this step of the trouble shooting guide does not apply since the fuel pump relay is good.
6. Kick down relay is the correct one (not a #53)
7. The spark plugs were wet with fuel, I pulled the fuel pump relay ( no fuel to rails confirmed by meter) pressed the pedal to the floor and cranked the engine. It stumbled once or twice then just rolled with no attempt to run. Replaced the fuel pump relay and had basically the same symptom (engine stumbles but no start).
So trying to reason out why I have fuel, spark but no start........ The LH is dumping too much fuel causing the cylinders to flood and since there is not proper atomization of the air fuel mixture it will not sustain running condition. Does that sound about right? Anything else to try? check?
Three Wheelin'
Joined: Feb 2004
Posts: 1,748
Likes: 357
From: St. Augustine, FL
Brent - you really should read my thread end-to-end. I had a two for one and lost the MAF and LH at the same time. On my thread, you'll find there were a super number of helpful people offering the EXACT same advice you'll get here.
My money is on the MAF/LH. They seem hypersensitive to electrical "Jumping" and I believe your situ is very much like the one I created for myself.
Good Luck!
My money is on the MAF/LH. They seem hypersensitive to electrical "Jumping" and I believe your situ is very much like the one I created for myself.
Good Luck!
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Joined: Feb 2002
Posts: 7,060
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From: Cambridge England
It may still be flooded - which is easy to do in cold weather.
Everything sounds basically OK, but when it has been left overnight and still won't start try:
Unplug MAF; this forces the LH into limp home mode with a fixed injector pulse. If it then starts, then MAF may be a problem, but once it has run and cleared itself properly, it may then run OK with the MAF reconnected.
Everything sounds basically OK, but when it has been left overnight and still won't start try:
Unplug MAF; this forces the LH into limp home mode with a fixed injector pulse. If it then starts, then MAF may be a problem, but once it has run and cleared itself properly, it may then run OK with the MAF reconnected.
Here is the latest. Following JDSPorsche trouble shooting list.
1. Car has fuel
2. No clicking noise when key is turn on without starting
3. I have strong spark on both cylinder banks
4. The fuel pump comes on then shuts off at 36lbs according to the fuel gauge that I have mounted on the injection rail (I know its low but I know why its like that and it's been like that when it ran)
5. this step of the trouble shooting guide does not apply since the fuel pump relay is good.
6. Kick down relay is the correct one (not a #53)
7. The spark plugs were wet with fuel, I pulled the fuel pump relay ( no fuel to rails confirmed by meter) pressed the pedal to the floor and cranked the engine. It stumbled once or twice then just rolled with no attempt to run. Replaced the fuel pump relay and had basically the same symptom (engine stumbles but no start).
So trying to reason out why I have fuel, spark but no start........ The LH is dumping too much fuel causing the cylinders to flood and since there is not proper atomization of the air fuel mixture it will not sustain running condition. Does that sound about right? Anything else to try? check?
1. Car has fuel
2. No clicking noise when key is turn on without starting
3. I have strong spark on both cylinder banks
4. The fuel pump comes on then shuts off at 36lbs according to the fuel gauge that I have mounted on the injection rail (I know its low but I know why its like that and it's been like that when it ran)
5. this step of the trouble shooting guide does not apply since the fuel pump relay is good.
6. Kick down relay is the correct one (not a #53)
7. The spark plugs were wet with fuel, I pulled the fuel pump relay ( no fuel to rails confirmed by meter) pressed the pedal to the floor and cranked the engine. It stumbled once or twice then just rolled with no attempt to run. Replaced the fuel pump relay and had basically the same symptom (engine stumbles but no start).
So trying to reason out why I have fuel, spark but no start........ The LH is dumping too much fuel causing the cylinders to flood and since there is not proper atomization of the air fuel mixture it will not sustain running condition. Does that sound about right? Anything else to try? check?
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From: Houma, LA.
I tried my spare MAF (no change)
Tried with MAF disconnected (no change)
I've waited 2 days without cranking (no change)
I could not have created the issue It's been sitting in my drive without moving for 6 months. I started it 2 weeks ago then a week ago (no start) Only thing that I did was charge the battery and as I stated in the beginning I did try to boost crank it using the charger but when it still didn't turn over fast enough I stopped, disconnected the battery, charged it for an hour thgen reconnected the battery and it started. That was the last time it ran.
Tried with MAF disconnected (no change)
I've waited 2 days without cranking (no change)
I could not have created the issue It's been sitting in my drive without moving for 6 months. I started it 2 weeks ago then a week ago (no start) Only thing that I did was charge the battery and as I stated in the beginning I did try to boost crank it using the charger but when it still didn't turn over fast enough I stopped, disconnected the battery, charged it for an hour thgen reconnected the battery and it started. That was the last time it ran.