1990 buick Regal 3800

[mulchman61]

Can anyone help me. I have 1990 buick Regal with a 3800 engine. She runs very well but lately she has been

surging at idle and sometimes stalls. I have the service engine light on. I down loaded codes i got a code 41 and a code 34

Can anyone shed some light on these. And do you have any info on testing the areas that the codes say need repair.

I am a preet good back yard mechanic and just need some guidance.

Thanks

[xtremerevolution]

Can anyone help me. I have 1990 buick Regal with a 3800 engine. She runs very well but lately she has been

surging at idle and sometimes stalls. I have the service engine light on. I down loaded codes i got a code 41 and a code 34

Can anyone shed some light on these. And do you have any info on testing the areas that the codes say need repair.

I am a preet good back yard mechanic and just need some guidance.

Thanks

 

Hi there!

 

First off, welcome to the boards.

 

Code 41: cam sensor circuit fault, igntion control circuit fault

 

Code 34: map sensor signal out of range, low

 

 

Here's a page for future reference:

 

http://www.extreme-check-engine-light-codes.com/GM%20OBD1%20Decoder.htm

[xtremerevolution]

Are you current on maintenance? Spark plugs, wires, etc.? Fuel filter?

[mulchman61]

Plugs and wires yes, Fuel filter not sure. Just gor car

[xtremerevolution]

Plugs and wires yes, Fuel filter not sure. Just gor car

 

Last time I got a code 41, I was running 4800 RPM going uphill in Colorado for 2 minutes straight on 85 octane cheap gas, and it threw a code when I got to the top. I re-filled with good gas and all was well afterward.

 

If the car has been sitting, you may have some water in the gas tank. Dump a can of seafoam in there for starters and see if that helps clean stuff out. Not a whole lot goes wrong with these 3800's. Check your wiring to make sure everything is connected properly, and check your vacuum hoses.

[mulchman61]

bump

[xtremerevolution]

bump

 

Have you checked the items I mentioned? Have you run seafoam through the car yet?

[mulchman61]

I have run seafoam in gas tank. Drove about 20 miles reset ecm. No change.

Have new wires, plugs and checked vacuum lines. Still there.

[mulchman61]

I have also cleaned MAF sensor, Tapped on back of maf. Engine ran steady, Gained access to ecm to check wiring that all looked tight. replaced air filter. I was told by previous owner that they replaced cam sensor about a year earlier.

Checked for any loose wiring or plugs, none. I here a lot about the magnet on cam shaft coming off. if thats the case would engine still run without cam sensor?

[Crazy K]

i think the engine would still run with a bad cam sensor.

[DaveFromColorado]

I had a 1990 Regal GS, with the 3.8 ... the cam sensor went bad long before I got the car, and for the year that I drove the car, I never bothered to replace it. She ran quite fine without it.

 

I kick myself in the butt all the time for selling that car.

 

--Dave.

[mulchman61]

OK guys i pulled the cam sensor and it looks like the magnet is missing. I removed bolt in balancer so i can remove balancer pulley. Does anyone no how to get pulley off crank.

[PROTESTtheHERO]

my 93 regal 3800 had the same symptoms but it was a bad throttle position sensor. the thing is if u have a scanner it should say "tps voltage low".