93 mtx. 126k miles.
I have noticed a hard-to-start pattern:
If the car sits for over 1.5 days, it will crank right up fine.
If the car is restarted within about 5 minutes of turning off, it will crank right up fine.
If the car is started any time between the 5 minutes to 1.5 days, it will turn over and over for a long time (~20 seconds) before it weakly catches and finally fires up, with VERY rich pure gas smell/smoke comes from the tail pipes.
Holding WOT during this cranking and it will fire up with a a second or two of cranking.
This condition has started about a year ago and has been getting worse with time.
Here lately, while holding WOT during cranking, itll will typically backfire (once) while cranking. These have been very loud and scare most bystanders! The back fires started about 3 months ago, and have been occuring more and more often now, that it will backfire (just once) about every-other crank attempt.
Now comes the crazy part-- Once the car is cranked up, it runs perfectly, idles fine, etc. No change in the performance at all. It is still my daily driver.
I Have tried replacing the ICM- no change. Changed air filter (went to K&N)- no change.
The rich fuel out the pipes and the required WOT tells me it is flooded beyond starting during those times.
The backfire also points to there beeing too much fuel(how it gets ignited in the intake, I do not know??? If the valve timing was off, would the engine still perfect??).
The odd time window makes some sence-- within the 5 minutes, it does not have time to sit and flood. after 1.5 days, any flooding has evaporated out.
I think this all points to leaky fuel injectors.. but could they all be leaking? could just one leaky injector cause these problems? seems like no.
The fuel pressure on the fuel rail checks out fine (within specs) with engine running and while off.
Any confirmations, ideas, suggestions? It has me confused.
Please HELP!
I have noticed a hard-to-start pattern:
If the car sits for over 1.5 days, it will crank right up fine.
If the car is restarted within about 5 minutes of turning off, it will crank right up fine.
If the car is started any time between the 5 minutes to 1.5 days, it will turn over and over for a long time (~20 seconds) before it weakly catches and finally fires up, with VERY rich pure gas smell/smoke comes from the tail pipes.
Holding WOT during this cranking and it will fire up with a a second or two of cranking.
This condition has started about a year ago and has been getting worse with time.
Here lately, while holding WOT during cranking, itll will typically backfire (once) while cranking. These have been very loud and scare most bystanders! The back fires started about 3 months ago, and have been occuring more and more often now, that it will backfire (just once) about every-other crank attempt.
Now comes the crazy part-- Once the car is cranked up, it runs perfectly, idles fine, etc. No change in the performance at all. It is still my daily driver.
I Have tried replacing the ICM- no change. Changed air filter (went to K&N)- no change.
The rich fuel out the pipes and the required WOT tells me it is flooded beyond starting during those times.
The backfire also points to there beeing too much fuel(how it gets ignited in the intake, I do not know??? If the valve timing was off, would the engine still perfect??).
The odd time window makes some sence-- within the 5 minutes, it does not have time to sit and flood. after 1.5 days, any flooding has evaporated out.
I think this all points to leaky fuel injectors.. but could they all be leaking? could just one leaky injector cause these problems? seems like no.
The fuel pressure on the fuel rail checks out fine (within specs) with engine running and while off.
Any confirmations, ideas, suggestions? It has me confused.
Please HELP!
