2002 S80 Bucking feeling at full stop

MikeDJr · Post by **MikeDJr** » 28 Aug 2013, 20:52

Hello everyone, new member here. Here is my problem.
My 17 year old son purchased an 02 S80, 2.9 with 146,000 miles. The car had a good CarFax report and appears to have been well maintained and the price was fair. Only problem is, it does have a CEL. We tried to read it when we looked at the car but could not get a code from my buddies portable scanner but the car ran very nice, and on the test drive didn't notice the below problem. I ordered an Autel scan tool but have not received it yet. Hoping these symptoms sound familiar.

First a couple things;
Test drove the car and really didn't notice the below problem. It seems to have gotten worst as I drive it. My gut feeling is the car was sitting for a while for sale. Bought the car with CEL on. When I got it home I disconnected the battery to correct it's improper installation by the previous owner. Obviously the CEL went off. Thought it was clear so took it to NJ inspection and failed due to Cat. (not ready) and Evap. (Not Ready). That night while driving the CEL came back on and is still on. The car does smell a little hot but gauge is reading normal.

Problem;
The care runs very smooth except when at a full stop. When stopped with foot on the brake, and also in park, the engine feels like it BUCKS, HESITATES, SURGES, but RPMs are solid at 700 and they don't move. I am not quite sure how to explain it. I have done many searches for the above key words but the results are always talking about a fluctuating idle. My idle is not fluctuating. Its solid! This happens with the AC on or off. If I hold the break, and throttle up to 1000 rpm's it seems to go away. Upon acceleration, both hard and smooth, the trans does not slip and downshifts nicely. Again, the car runs great except for the this jerking problem.

Please tell me it's not a slipping trans. I am stumped. Hopefully I get my Autel tomorrow and find a code. I am hoping I didn't steer my kid wrong because thats gonna cost me!

Any help at all would be greatly appreciated.

Post by **matthew1** » 29 Aug 2013, 10:21

This may not solve it but will help diagnose the problem: do a Stage 0, attention on the big three things an engine needs: fuel, spark, air.

In other words, put new spark plugs in, check / replace plug wires, check / replace air filter, run some (quality) fuel / injector treatment through her.

matt5112 · Post by **matt5112** » 02 Sep 2013, 07:20

Also consider reading this: https://www.matthewsvolvosite.com/forums ... hp?t=17252

MikeDJr · Post by **MikeDJr** » 02 Sep 2013, 10:48

Thanks Matt
So I took your advise and started a Stage 0 service. Yesterday changed the fuel filter, oil and filter, air filter, spark plug boots, I bought new plugs but the ones in the car had already been changed in January and are Volvo plugs. They looked brand new so left them.

So I got my scanner. We have 2 codes,

P2096 - Post Catalyst Fuel Trim System Too Lean Bank 1

P2098 - Post Catalyst Fuel Trim System Too Lean Bank 2

And 3 not ready modules,

Catalyst monitoring - INC
Evap system - INC
Oxygen sensor Monitoring - INC

I am thinking about starting my search for a bad 02 sensor. What do you guys think.

Mike

Post by **matthew1** » 02 Sep 2013, 11:32

I'd run some quality fuel injector cleaner though it, reset codes, and report back after a tank of premium.

BeardedEagle · Post by **BeardedEagle** » 07 Dec 2013, 11:03

Have you had any luck solving your problem? I am having similar issues. As well as erratic idle.