97 850R sluggish acceleration

clawless · Post by **clawless** » 27 Jun 2007, 08:22

Hello All,

Thank you all for the great info here! I have done a few searches and have come up with nothing on my current issue. Of recent my 97 850R has had an intermittent acceleration problem. When I get on the gas hard, it feels like the there is a slight miss, maybe across all cylinders or a breakup in the ignition. Its not smooth at all. The all of a sudden it clears up at higher rpm, nothing consistent, but usually over 3K. Sometimes it does not clear and the rough accel remains through out the rpm range. Sometimes (very rare) there is no issue at all and it

Trilarry · Post by **Trilarry** » 27 Jun 2007, 09:16

Two things come to mind for your acceleration issue: fuel filter and air filter. Your tuneup would be complete and this would be 2 things to rule out.
Tri

clawless · Post by **clawless** » 27 Jun 2007, 09:42

Thanks Trilarry...good point...

You know I bet that fuel filter has never been changed. When I got the car it had 52K on it and still had the factory 'tuneup' parts, not long after I got it, it started miss firing bad, CEL and everything, I did a full tune up, it was much better, ran great actually. I will pick one up tonight. the air filter is a K&N cone filter, it was cleaned several months ago, it looks OK but I will clean it again anyways to be sure

As a side note that may be the lean condition CEL as well... that would make me not so happy if ~$20 filter was the cause all along....I will let you know!

clawless · Post by **clawless** » 28 Jun 2007, 07:33

Well the CEL came on again yesterday driving home. I replaced the fuel filter, it was the original. It seems better however it seemed better after I replaced the other components. I cleared the light and will give it another day and see what happens...

Trilarry · Post by **Trilarry** » 28 Jun 2007, 08:14

It is better because now you have a date when it was changed and you can have a little peace of mind because fuel filter can now be ruled out. What was the code on the CEL...lean fuel? I hope you got a good fix.

Tri

clawless · Post by **clawless** » 28 Jun 2007, 18:02

Well on my trip home the sluggish accel started again and the CEL came back on. The code is P0171 system too lean bank 1.

I also forgot to mention that I have changed the injectors (grean giants). The sluggishness was present before and after the change.

ideas??

thanks!

britdirk · Post by **britdirk** » 28 Jun 2007, 18:26

I had a similar problem, and i replaced the fuel pump. see my post on this site for more details on my problem: 1997 850R Shutter and stall
Maybe this will help.
Good Luck

Trilarry · Post by **Trilarry** » 28 Jun 2007, 20:18

Clawless, I just copied this insert from the 850 Manual that's free on the top of this forum. It pertains to your code 171. (2-3-1 or 2-2-3) Try these prescribed checks and see if you can run down the problem. Work around the Breakout Box instruction.
Tri

Code 2-3-1 (Long Term Fuel Trim Partial Load) Or
Code 2-3-2 (Long Term Fuel Trim Idling)
1) Check for other codes. If Code 3-1-5 is stored, perform
testing on that code first. If Code 3-1-5 is not stored, go to next
step.
2) Check status message on Volvo Scan Tool (998-8686). If
status message reads LOWER LIMIT, go to step

. If status message
reads UPPER LIMIT, go to next step.
3) Turn ignition on. Connect voltmeter between MAF sensor
connector terminals No. 2 and 4. If voltmeter reads .1-.2 volt, go to
next step. If voltmeter does not read .1-.2 volt, test using new MAF
sensor.
4) Check for air leakage in intake system. Repair as
necessary. If air leakage in intake system is not present, go to next
step.
5) Check for air leakage in exhaust system. If there is no
air leakage, go to next step. If there is air leakage, repair as
necessary.
6) Check fuel and residual pressure. If fuel and residual
pressure are okay, go to next step. If fuel and residual pressure are
not okay, repair as necessary.
7) Connect breakout box to ECM and check ground connections.
See COMPUTERIZED ENGINE CONTROLS in I - SYSTEM/COMPONENT TESTS
article. Reconnect ECM. Repair as necessary.

If status message reads LOWER LIMIT, turn ignition on.
Connect voltmeter between MAF sensor connectors terminals No. 2 and 4.
If voltmeter reads .1-.2 volt, go to next step. If voltmeter does not
read .1-.2 volt, test using new MAF sensor.
9) Check for air leakage in intake and exhaust system. Repair
as necessary. Check fuel and residual pressure. Repair as necessary.
If no air leakage and fuel and residual pressure are okay, go to next
step.
10) Remove hose leading to intake manifold from EVAP valve.
Connect vacuum pump to EVAP valve coupling. If vacuum gauge does not
show stable vacuum, repair as necessary. If vacuum gauge does show
stable vacuum, go to next step. Check engine oil and fill as
necessary.
11) Start engine and run at idle a few minutes. Using Volvo
Scan Tool (998-8686), read off value on SHORT TERM FUEL TRIM and note
value. Disconnect and plug crankcase ventilation. Read off value of
short term fuel trim once again. If value is more or less unchanged,
go to next step. If value rises, engine oil is diluted with fuel.
Repair as necessary.
12) Connect breakout box to ECM connector and check grounds.
Connect ECM. Check all signals to and from ECM. Repair as necessary.

clawless · Post by **clawless** » 05 Jul 2007, 19:18

Trilarry...I downloaded that manual and did not find this passage, thanks!

I looked over this and decided that a trip to the local Volvo shop (not the dealer) was the way to go. They plugged the fancy Volvo code reader and got 2-3-1. Nor sure if it was upper or lower limit, (assuming lower from the other code) I will check tomorrow. Anyway they checked the fuel pressure, it was fine, the MAF is new, checked for vacuum leaks and checked the oil (you know my last oil change was semi-synthetic any problem with that?) so the other thing was to reset the fuel trim adaption program, which they did.

we will see.....

As far as the acceleration issue, I think I have solved that and am somewhat embarrassed. Turns out there was another intermintant vac leak under the dash where I connected my aftermarket vac / boost gauge. It was very slight , but I noticed that it was pulling a little low and fluctuating while sitting in traffic so I checked it. Its all tight now. This had no effect on the CEL though.

adrian22 · Post by **adrian22** » 05 Jul 2007, 20:07

if you use K&N cone filter- the oil can get deposited on the MAF and clog it
You can remove it an spray it with cleaner-Do not touch it it is sensitive