I am trying to fix this little throttle prob. before I sell my car. Teh diagnostic is now saying code 172, which I believe is rich. Ever heard any thing about the throttle position sensor? Do you have a list of the codes #'s and what they mean?

 

No I don't have a code list any more and don't have access to one anymore.I forget exaltly what year your car is if it is pre OBDII im going to insert a link into this post for you to look at.I have seen many throttle position sensors go bad in the past.Also make sure that none of the vaccum lines are cracked or broke.Also make sure you chek the one behind the power steering pump on the end of the intake.
http://www.troublecodes.net/Volvo/

See if this helps if not I will see what else I can do for you.

 

Tech, thanks for the help. I have been working with a buddy of mine trying to diagnose this problem before I sell my car. He thinks that the pulse in the throttle is probably the throttle position sensor. Would that create the symptoms I have been speaking of in previous messages? It rarely does it, and only while on the highway at a constant speed ( holding the pedal steady). Also would this problem pull up a rich code? As for the asking price for my car, do you think that price is fair as the car is in perfect mechanical and near perfect visual condition? I have added over $1600 in parts and upgrades, and the blue book is $4850.

 

The Throttle position sensor could cause the problem you are having.Im not sure if it would throw a code for running rich though.Usually if the throttle position sensor goes bad you will feel most problems like a transmission shifting really weird.Im not sure what else to advise you on It's kinda hard to come up with more with out being there to see what things are doing.As for the price you are asking I think it is a very fair price.

 

Is there anyway I could test the throttle position sensor, so that I don't continue buying parts I don't need. I already wasted $200 on a MAF that I didn't need. btw, how much should I charge for a perfect bosch MAF for th e94 850 turbo?

 

If you ever found a wiring diagram you could find the proper wire and hook up an ohm meter and open throttle body slowly and watch the numbers and see if they drop off at all during the sweep.Are you trying to seel your old mass flow sensor or the new one?If you are selling the old one I would say $150.00 if it is the new one sell it for what you payed for it.You only had it on for a short time.

 

Tech, I was thinking that the feeling in the throttle does resemble the tranny shifting. In your previous message, you stated that it would feel like the trannie was shifting weird. Would it only do this when it is shifting, or would it do it at random while driving w/out shifting? Again thanks for all your help. I found that volvotechinfo.com sells individual diagrams and service sections. The throttle position sensor is $88 and I want to be very certain before I get it. I have talked to several people who feel this is most likely my problem

 

The transmission uses the info from the throttle position sensor to know when to shift.Kinda like the kickdown cable on the older cars.Also if the throttle position sensor looses signal any time it will affect how the car runs.It supplies signals for many things.

 

Hey tech, I am going to run diagnostic tomorrow to see what sensor tripped. I am gonna buy a throttle position sensor and take it with me to my friends just in case that's what it is. Can you tell me where the sensor is? I need a part # to get it.

 

Remove the black cover that hides the throttle cable.And the throttle position sensor is mounted on the throttle body.I believe it is on the bottom side of the throttle body.You may need a mirror to get the # off of it with out removing the throttle body.It is a lillte black box looking thing on the throttle body with a plug going to it.

 

Tech, in removing the cover, I found two count them two vaccum lines with huge gaping holes in them. I didn't even realize there were lines under there. Hopefully I will be able to replace those two elbow lines and fix it. Would these lines right around where the throttle cable linkage is cause the problems I have stated? And where can I get those small 1/8 id elbow lines?

 

Yes they would cause your problems.You can either get them from the dealer or just use some good vaccum line to replace them.With those holes in those elbows it is allowing alot of extra unmetered air into the engine causing it to run very rich causing problems.

 

Ok, so i fixed the lines, and the problem is still there. Might I have to reset the check engine light?

 

Yes you have to reset the light and might be a good Idea to disconnect the battery for about 15 min to reset the computer.The computer is still thinking the fault is there.

 

I also have a question about a driver side turn signal. Where can I find one. Mine was broken during Hurricane Ivan, as was the passenger side wiper arm.

 

Sorry Beth you might have to go to the dealership or e-bay.I have checked all the parts sites I know and they are not avalible in the aftermarket yet.

 

Ok so the throttle position sensor is working properly. Smooth transition with no drop off. What are the odds that it is either a clogged or bad cat. converter, or bad o2 sensor, how could I check the o2 sensor, and is there anyway to check a cat?

 

in addition to my previous questions, how do you reset the check engine code without the diagnostic box?

 

Im not really sure with out the book on how to check the O2 sensor.To check the cat feel the exhaust coming out the back and make sure you have good flow out the back.If a cat gets clogged it reduces the flow out of the exhaust.You should have have the OBD under the hood correct?You can clear the code there.If you have OBDII which is inside the car you need a scanner to clear it.Then you could also watch the O2 sensor if you had the proper scanner.

 

Looked at the plug wires and one wire has a large slit in the insulation, and the wire immediately next to it has been taped up. I think the problem might have been a misfire. The rotor button also looks pretty worn.