Stupid Question Check engine light?

Crankin · Post by **Crankin** » 28 Mar 2007, 01:03

Hey Guys

I just picked up A 94 850 Turbo Wagon, it has 194,000 km on it seems to run pretty good I did however notice a very slight shift in RPM while accelerating slowly up to any speed you can just feel the car rock a little bit back and forth while you accelerate slow. If you get on it, it goes like stink. Also the check engine light has come on. NOW here is the stupid question The check engine light is the triangle with the little green thing in it right? To me it almost looks like a little green man walking, is that what I'll be doing soon ? Do you think this accelerating thing has any thing to do with the light being on? If I were to guess though I would think That this slight accelerating thing would be a small leak in the turbo line somewhere.
What do you guys think? Any similar problems?
Oh you can actually see the RPM vary mabye 100 RPM while accelerating.

Thanks

Crankin

Post by **Ozark Lee** » 28 Mar 2007, 07:02

Hi Crankin,

The light you described is the Lambda Light. On US domestic cars it is labeled as the Check Engine Light but it is the same thing.

The "CEL" is likely indicating a problem that is causing the poor performance you are describing. The good news is that, since your car is a '94, you have all of the diagnostic tools built into your car. Pull your codes from Sockets A-1 (transmission), A-2 (engine fuel management) and A-6 (engine ignition) and post the results.

Here is how to read the codes:

http://volvospeed.com/CheckEngine.php

...Lee

Crankin · Post by **Crankin** » 29 Mar 2007, 00:06

Hi Lee,

Thanks for your response. I got code 436 which is Rear heated oxygen sensor compensation? What does this mean? For my first tank of gas I put in midgrade gas only because I saw the salesman throw in the cheap stuff for the test drive. Would that do that? I did reset the computer and it didn't come back on yet in about 65 km. Maybe it was a spike or something? It does how ever still do that slight surge thing while accelerating? What do you think any suggestions?

Thanks

Crankin

Post by **Ozark Lee** » 29 Mar 2007, 06:59

The surging/hesitation you describe could be caused by a number of things but I would start with the easy stuff.

First, particularly on a turbo, check all of your vacuum lines for cracks, splits, leaks.

Next, I would clean the throttle body with carburator cleaner and the clean the MAF (AMM) sensor with MAF cleaner. On the MAF sensor just spray it and let it dry, don't touch it or scrub it in any way.

...Lee

Crankin · Post by **Crankin** » 01 Apr 2007, 08:55

Hi Lee,

Sorry I didn't reply so quickly I cleaned the T B last night and plan to clean the MAF tonight at work, I was going to do it last night but I didn't know they were th saftey torx bits. Looks like another trip to the store for the bits. It looks like it made a little bit of a difference for the surging, it was very dirty in there even the hose leading into the T B was really gooey. I put a little spray into that to clean it. That secondary hose that is about 1 inch that goes into the T B hose what is that? I didn't want to get to carried away with spraying things I don't want to damage the hoses, can the spray damage the hoses? Also for the turbo hoses I noticed the 3 inch hose off of the intercooler didn't have a clamp. It didn't seem to make a difference after I clamped it. Is there any where on the world wide web of a diagram of the turbo system? I looked at all of the lines and hoses and everthing looked okay but I don't know your eyes get buggy after a bit

I did also notice a little half inch hose off the top of the motor on the right top was just cut off? there did seem to be a little bit of air coming out of it? Have you ever heard of this? what could this be for?

Sorry for all the questions I. am the sky is falling kind of guy, so I usually think the worst I hope your suggestions work

Thanks

Crankin