gjmascoli
11-04-2017, 03:26 PM
Hi folks, been away for a long while but still driving the 1990 e34, now with 246k miles.
M20 engine, 5-speed
Cold start always requires 2-5sec of cranking for the past 7 years.....I think maybe need a new fuel pressure regulator, but I've ignored this. Starts right up when warm.
Over the past year or so I seemed to have hesitation under load, but only on cold and wet mornings. Often coincided with a nearly empty fuel tank so I always thought moisture in the fuel lines....cleared it up with some fuel line drier into the tank.
Recently (last 4-6 weeks) the hesitation and rough running under load was still intermittent but happening more, always in the morning and within the first 5-10 miles of driving. Symptoms seemed to be similar to a possible slipping clutch, but the car stalls instantly if I release to clutch in 2nd gear while stationary. NOTE: clutch may be original with 246k miles. I haven't replaced and I bought car with 175k.
Very occasionally CEL will illuminate, used to be just a flash, now it stays on for 5-10sec and then goes off. Seems to come on more often recently.
This past week fuel mileage has dropped from 21mpg to 18.5mpg all on my normal drive to/from work on backroads.
TODAY: 5 miles into drive this morning (dry morning but 40F) the car starts hesitating and running rough as I traveled up a slight incline. About 1 mile later on flat ground engine stalled. I pulled over, waited 5 minutes, cranked engine, started right up, and drove home with no issues. Many red lights along the way, no issues, ran fine.
Checked the Crank Position Sensor resistance between prongs 1 & 2. Got 0 Ohms vs spec 540+/-10%.....so the CPS seems shot. BUT: car starts with the CPS plugged in, car ALSO starts with CPS unplugged....idles fine in both instances, so this seems weird to me.
Stomp Test threw the 1221 code today - O2 Sensor (I do smell gas, running rich)
I don't seem to have vacuum leak, I check by spraying Carb cleaner on various vacuum hoses.
So:
1) I will replace 02 sensor based on stomp test
2) Why is the computer not also throwing 1243 -Crank Pulse Sensor?
3) the CPS is cheap, will replace, BUT can anyone tell me why a bad CPS is not causing me more grief? Seems I shouldn't even be able to get the car started.
4) I will replace the fuel regulator....I assume that will help the cold start by keeping the fuel lines pressurized
5) Some google searches also mention Idle Control Valve, should I bother? I don't usually just throw parts at a problem
6) Have also seem posts about the Brake Booster drain getting plugged and water being drawn into the Intake....since I have often had the problem on cold and wet conditions, is this a legitimate issue? How to check that drain?
7) I think the clutch is fine
Thoughts?
M20 engine, 5-speed
Cold start always requires 2-5sec of cranking for the past 7 years.....I think maybe need a new fuel pressure regulator, but I've ignored this. Starts right up when warm.
Over the past year or so I seemed to have hesitation under load, but only on cold and wet mornings. Often coincided with a nearly empty fuel tank so I always thought moisture in the fuel lines....cleared it up with some fuel line drier into the tank.
Recently (last 4-6 weeks) the hesitation and rough running under load was still intermittent but happening more, always in the morning and within the first 5-10 miles of driving. Symptoms seemed to be similar to a possible slipping clutch, but the car stalls instantly if I release to clutch in 2nd gear while stationary. NOTE: clutch may be original with 246k miles. I haven't replaced and I bought car with 175k.
Very occasionally CEL will illuminate, used to be just a flash, now it stays on for 5-10sec and then goes off. Seems to come on more often recently.
This past week fuel mileage has dropped from 21mpg to 18.5mpg all on my normal drive to/from work on backroads.
TODAY: 5 miles into drive this morning (dry morning but 40F) the car starts hesitating and running rough as I traveled up a slight incline. About 1 mile later on flat ground engine stalled. I pulled over, waited 5 minutes, cranked engine, started right up, and drove home with no issues. Many red lights along the way, no issues, ran fine.
Checked the Crank Position Sensor resistance between prongs 1 & 2. Got 0 Ohms vs spec 540+/-10%.....so the CPS seems shot. BUT: car starts with the CPS plugged in, car ALSO starts with CPS unplugged....idles fine in both instances, so this seems weird to me.
Stomp Test threw the 1221 code today - O2 Sensor (I do smell gas, running rich)
I don't seem to have vacuum leak, I check by spraying Carb cleaner on various vacuum hoses.
So:
1) I will replace 02 sensor based on stomp test
2) Why is the computer not also throwing 1243 -Crank Pulse Sensor?
3) the CPS is cheap, will replace, BUT can anyone tell me why a bad CPS is not causing me more grief? Seems I shouldn't even be able to get the car started.
4) I will replace the fuel regulator....I assume that will help the cold start by keeping the fuel lines pressurized
5) Some google searches also mention Idle Control Valve, should I bother? I don't usually just throw parts at a problem
6) Have also seem posts about the Brake Booster drain getting plugged and water being drawn into the Intake....since I have often had the problem on cold and wet conditions, is this a legitimate issue? How to check that drain?
7) I think the clutch is fine
Thoughts?