Tommybeach

rough running and poor start up

Recommended Posts

My car was performing perfectly, until I pulled through some tall grass. It was just loose farm grass, that I slowly drove through. I switched off my Reatta for a few minutes. When I started it, there was no start problems, but it immediately began to run roughly, like it wanted to cut off. I gave it a little extra fuel and it kind of lunged, like it had bad gas. I drove it home ( about a mile ) expecting the problem to clear, but it did not. The next day, I drove to the gas station and put in some high octane, still thinking it was something in the gas, but it did not help. The following day I started to the garage to have it checked out. I didn't make it. It cut off, and restarted a couple times, until it refused to crank. I rented a dolly and took it to the shop, thinking the mechanic would quickly identify my problem. That was weeks ago, and several parts later.. So far I replaced the fuel pressure sensor, mass air module, and some other little sensor ! The mechanic told me to ask for your help, because he did not want to guess any more ... Does anyone have any ideas ?

Share this post


Link to post
Share on other sites

Common symptoms of a bad Ignition Control Module (ICM) or a bad Crankshaft Position Sensor. Look for green/gray goo on the side ICM as shown in the photo below. It's a sign that it's bad.

 

ICM-magnavox-goo.jpg

Share this post


Link to post
Share on other sites

thanks Ronnie,  by the way, I got hooked on the Reatta fever, when I lived in Knoxville ..... I was testing new cars... I drove a 1991 Reatta, and then drove to West Knoxville to test drive a new BMW.... After driving the BMW I rushed back to the Cadillac dearlership on Alcoa hwy--- the Reatta was pulling out when I got back to the lot... I told the salesman that I wanted to buy the Reatta when it got back from the "test drive" . The salesman smiled at me, and said, " it isn't coming back" , I just sold it !  When I moved back to South Carolina, I told my cousin about the Reatta... his son in law owns a car lot.... and he found me one about 10 years ago... I love it !

Share this post


Link to post
Share on other sites

It's rare to see a Reatta in this part of the country now. I live about 40 miles west of Knoxville. I go to cruise-ins and car shows pretty often in Knoxville.  It's been a couple of years or more since I saw one besides mine.

  • Like 1

Share this post


Link to post
Share on other sites
52 minutes ago, D-a-n-i-e-l said:

Check for grass or damage from said grass around cps

That's my guess too. I once drove through deep water with the Red. Car died and took awhile to starg again. You didn't say what year Reatta you have but if it is an '88 to '90  Ronnie could also be right, but I would start with the Crank Sensor.

Share this post


Link to post
Share on other sites

thanks for your answers ...my Buick Reatta is a 1990---  it was running great !  Just wondering... how does grass have an effect on the crank sensor ? I am new to all this electronic system stuff...

I drove this car for years before having a problem.... I guess I should have known better than to drive through the grass, but it didn't appear to thick or, even too high . My first problem occurred 3 years ago. It was at night, and I ran over a coon. The lights went off, and then back on... I drove home, with no problems.

The following day,  I put my Reatta on a lift, and inspected it for damages. Nothing was found, but shortly afterward, the dash light cluster began to go off, followed by cranking problems. I replaced a cracked cam shaft pulley and cam shaft sensor. This was followed by replacement of oil pressure sensor, mass air flow sensor, fuel pressure filter. Replaced ABS system completely. Replaced climate control unit. Replaced cruise control module , and climate control module. 

 Next radiator, thermostat, and water temperature sensor. Replaced battery and alternator. 

I had the old changed and the person over filled the engine. He installed one quart too much, and he did not drain it out. It seems like every time I have every thing working ( except the dash cluster going off and on ) something else will break... 

Reatta passnegers side.JPG

Share this post


Link to post
Share on other sites
20 minutes ago, Tommybeach said:

Just wondering... how does grass have an effect on the crank sensor ?

 

The back of the harmonic balancer has a notched shutter ring that runs closely through a gap in the crankshaft position sensor. If grass got caught in the notched ring and pulled into the sensor it could move or damage the sensor.

 

crank_sensor.jpg

  • Like 1

Share this post


Link to post
Share on other sites

Did you check for a clogged air intake ? That was my first though when you said "tall grass".

  • Like 1

Share this post


Link to post
Share on other sites
4 hours ago, padgett said:

Did you check for a clogged air intake ? That was my first though when you said "tall grass".

I checked the air intake blower and duct 

Share this post


Link to post
Share on other sites
13 hours ago, DAVES89 said:

Was this fixed and then running great?

Dave, 

my Reatta, was in the shop for the most part of April through August 6th.... Somehow my rear tire got a leak in the rear tire..... the mechanic returned my car and the following morning , I aired up the tire and drove it the closest tire shop. My car ran perfect during the drive to the shop !  At the shop I parked my car outside and the man repaired my tire as I set in the lounge. He came in from a side door and told me my car was  ready. I paid the bill and went out the door he came in... he had obviously driven my car... and when I went to crank it..... it cranked and cut off.. I had to hold the gas pedal down to keep it cranked... looking at the dash displays... it appeared the oil pressure was too low to maintain idle... This is the same problem I have had twice prior.... I have replaced most items... so I am thinking it most be centered around the oil pressure .  The start of this problem was a couple years back after and oil change. I found the shop had put in too much oil ( 1 qt over fill ) 

Share this post


Link to post
Share on other sites
4 hours ago, Tommybeach said:

my Reatta, was in the shop for the most part of April through August 6th....

 

Sounds to me like you need to find a new mechanic. Keeping a car that amount of time for repairs is ridiculous.  Low oil pressure doesn't keep an engine from running unless there are some serious mechanical problems that are causing the engine to seize up.  If that were the case it wouldn't be running good part of the time.

Share this post


Link to post
Share on other sites

Ronnie, 

thanks for responding.... can you tell me what would cause the oil pressure to drop when the car is idling ? The problem is not all the time, but once it starts to occur, it does seem to get worse.  I have not gotten to enjoy my car for a couple years... My dash cluster was also going off, when I took it to the shop... for now it is working again, and that allowed me to see the drop in oil pressure when I took my foot of the gas pedal .

Share this post


Link to post
Share on other sites
39 minutes ago, Tommybeach said:

can you tell me what would cause the oil pressure to drop when the car is idling ?

 

It could be the oil pressure sender giving a false reading. It's very common for those to go bad on the 3800 engine.  Mechanically it could be a bad oil pump or bad rod bearings or main bearings.

 

If the pressure drops sporadically I would bet it's the oil pressure sender. If the oil pressure is normal when the engine is cold and then consistently drops way low when the engine is hot it could be a bad bearing or oil pump.

 

You say the pressure is low. What is the reading on the gauge when the engine is when warmed up after it has been driven for a while? Do you hear any knocking noises coming from the engine when the pressure is low?

Share this post


Link to post
Share on other sites

The engine sounds and runs perfect driving down the highway....  I drove it to the store 0% problems.... got out ... guy fixed my leaky tire....the car was moved and perhaps he drove it down the road... I don't know.... when I got back in ... the fuel low had come on (1/4 tank left ) and when I cranked the car, it began to run rough again ( just like when I put it in the shop back in April ) I looked at my gauges to see if anything else was off, and that is when I noticed the oil pressure was showing way low.. but when I pressed the accelerator down, the oil pressure when back to normal, and the motor ran smooth.... the problem here is I have to keep the accelerator pressured down, so when I put the car in gear, it lunges because the rpms are up. There are never any motor noises or any problems with the transmission either.... only the rough running which I associated with the low oil pressure shown on the instrument gauge. Is it possible for the gauge to be bad, or the pressure line to be stopped up ?

 

Share this post


Link to post
Share on other sites
22 minutes ago, Tommybeach said:

do you know what the correct part number is for the oil pressure sending unit ?

 

1988-1990 ACDelco D8046 Professional Fuel Pump Switch and Engine Oil Pressure Gage Sensor Assembly

ACDelco D8046

 

 

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now