91 Buick Hard start

[arvin_m]

Hello,

My 91 Buick Regal Custom starts fine most mornings with the first turn of the ignition, after I drive it for a while (and if it sits for a while) it takes 2 or 3 turns of the ignition to start. I have had it tuned up, fuel injector cleaned etc. I recently had the water pump replaced. Can someone help me figure it out, my mechanic told me to have the fuel injector cleaned and still no change.

I see from other posts not quite like my problem, fuel pump going bad, or cam sensor defective. Coud it be that?

I also hear this click and nothing happens and then I try again and it starts, sometimes 2-3 tries.

[arvin_m]

Originally Posted by arvin_m

Hello,

My 91 Buick Regal Custom starts fine most mornings with the first turn of the ignition, after I drive it for a while (and if it sits for a while) it takes 2 or 3 turns of the ignition to start. I have had it tuned up, fuel injector cleaned etc. I recently had the water pump replaced. Can someone help me figure it out, my mechanic told me to have the fuel injector cleaned and still no change.

I see from other posts not quite like my problem, fuel pump going bad, or cam sensor defective. Coud it be that?

I also hear this click and nothing happens and then I try again and it starts, sometimes 2-3 tries.

Well I have not heard from anyone, I went ahead and replaced the starter, that did not solve the problem. It sometimes starts with the first turn of the ignition and then sometimes it does not, it takes 2-3 turns (it does fire up but then cuts out) of the ignition but once it starts it runs good. My mechanic told me it is not the fuel pump or the Cam sensor as he checked for the proper fuel pressure.

So right now I'm back to square one....Any ideas would be much appreciated.

[tomogchi]

Is it normally happening on a cold morning? Does your dashboard dim out? When it takes the 2 - 3 tries to start, and it finally starts cranking, is it a slow whurring noise that you hear while the car starts?
Bill

[arvin_m]

Originally Posted by tomogchi

Is it normally happening on a cold morning? Does your dashboard dim out? When it takes the 2 - 3 tries to start, and it finally starts cranking, is it a slow whurring noise that you hear while the car starts?
Bill

Tomogchi,

No it's not just on a cold morning but all the time, the dash does not dim out when I crank or turn the ignition. Sometimes it will start with one turn of the ignition other times it takes 2-3 . I replaced the starter, just this morning I replaced the fuel filter, it has a new water pump, new alternator.... when it tries to start sometimes it is rough and then settles, I give extra gas and it starts to run smooth...I thought it was something to do with pressure build up in the tank, I release the pressure by opening the gas tank cap...no change at all....could it be the gas I buy from 76? if they have changed the additives etc. I will try that next, by buying gas from some other gas station....otherwise my mechanic told me he cannot think of anything....cam shaft sensor is fine, fuel pump has enough pressure...he is baffled so am I!

What are the symptoms of a bad Mass Air Flow sensor? or any other sensor like the Oxygen sensor....and where are they located on this car?

[tomogchi]

Your o2 sensor is located on the rear exhuast manifold. You should be able to see a single wire connected to a plug hanging on the center (give a little to the passangerside) firewall. if you follow that down to the manifold, you will see the 02 sensor, but i do not beleive that this is part of your problem. Biggest thing you will see from a bad o2 sensor is possibly a code and poor gas milage. and as for the map sensor im not exactly sure, but i beleive that is located on the firewall as well. And gas would not make your car the way it is. Worst you would hear is the "ping" on acceleration fromregular (87 octane), but i have never heard that in my vehicle. and Have you tried getting your battery checked at your local autoparts store? (autozone and advanced auto do it for free) its a long shot but maybe you dont have enough cranking amps (<--for the starting issue). Does your car throw any codes periodically? like the service engine soon light comes on and will then turn right back off (when the vehicle is on)? This soudns tupid, but have you tried replaced your pcv valve or small stuff like that? there could be a vacuum leak in your engine.
Sorry for the long responce
Bill

[arvin_m]

Originally Posted by tomogchi

Your o2 sensor is located on the rear exhuast manifold. You should be able to see a single wire connected to a plug hanging on the center (give a little to the passangerside) firewall. if you follow that down to the manifold, you will see the 02 sensor, but i do not beleive that this is part of your problem. Biggest thing you will see from a bad o2 sensor is possibly a code and poor gas milage. and as for the map sensor im not exactly sure, but i beleive that is located on the firewall as well. And gas would not make your car the way it is. Worst you would hear is the "ping" on acceleration fromregular (87 octane), but i have never heard that in my vehicle. and Have you tried getting your battery checked at your local autoparts store? (autozone and advanced auto do it for free) its a long shot but maybe you dont have enough cranking amps (<--for the starting issue). Does your car throw any codes periodically? like the service engine soon light comes on and will then turn right back off (when the vehicle is on)? This soudns tupid, but have you tried replaced your pcv valve or small stuff like that? there could be a vacuum leak in your engine.
Sorry for the long responce
Bill

Bill,

Thanks for your message, you are right about the gas part, I was also thinking about the battery, I will check it out....but if a battery is defective it will do it (in other words give me the slow crank) at the first crank, I do get to turn the engine... it looks like there is not enough fuel or the timing is off... now I have not checked the PCV valve or the EGR, I took it to a a tune up shop and hope they did all that, I love to work on cars and have a 63 Ford Falcon which is so nice to work on....by profession I'm an Electrical Engineer working in the Telecom industry...these intermittent problems are the worst... and I have so little time on the weekends these days...

The car does not show any OBD codes, before I could start the car by turning the ignition and no foot on the accelator pedal, now I need to push the gas pedal a little to get it going...is there some relay or some adjustment in the linkage which needs tightening?

Thanks for your help, I will look into the obvious, like yesterday I once again replaced a fuel filter and that did not change the situation....

You mentioned vacuum leak, can you tell me where to start looking for it, I don't have a shop manual, I plan to purchase one soon..

-Arvin

[mikelund]

Order a full shop manuel from Helm, Inc. Cost around $100. Has all the trouble shooting flow charts and specs. Plus great diagrams of where parts are located and what they look like. With my 91 Regal I just had the coils, wires and plugs changed. Made a great difference in the running especially under load. Not much difference in starting though. Its a 14 year old car. Replace the vacuum hoses you find, and the connectors. You may want to change the positive cable for the battery, internal corrosion possible.

[arvin_m]

Originally Posted by mikelund

Order a full shop manuel from Helm, Inc. Cost around $100. Has all the trouble shooting flow charts and specs. Plus great diagrams of where parts are located and what they look like. With my 91 Regal I just had the coils, wires and plugs changed. Made a great difference in the running especially under load. Not much difference in starting though. Its a 14 year old car. Replace the vacuum hoses you find, and the connectors. You may want to change the positive cable for the battery, internal corrosion possible.

Mike,

Thanks for the tip, I had a tuneup done changed the plugs etc.....but now I suspect it was not done right...regarding vacuum hoses, I need to know what is going where and I need to get a good shop manual....I will check the battery terminal and the battery again...

I noticed there is one part broken...it looks like a cable going into the engine block on the driver side of the car just under the air intake hose. The cable has this metal tube bolted to the block...it is broken at the base...don't know what it is? any clue?