The message to which you are about to reply is shown first. GO TO REPLY FORM



 VIEW    REPLY TO THIS MESSAGE    PRINT   SAVE 

1990 740gl non-turbo SOHC Hunts up and down in RPM while holding staedy throttle 700

Still chasing this problem on my 1990 740GL non-turbo that has 250k on it.

Car starts right up, idles fine. Hold the accelerator down slightly to add a steady amount of throttle and the engine starts to hunt up and down in RPM.

Things I've checked or done.

Vacuum leaks
cleaned IAC valve
replaced TPS and adjusted switch
cleaned throttle body and new gasket

A while back (maybe a year ago) replaced in tank fuel pump)

kind of starting to suspect the catalytic converter being plugged. On one of my last trips with the car, the fiberglass packing started unraveling out of the tailpipe. Assume that was the packing from the muffler and wondering if it was somehow related to something going on with the catalytic.

My next move was going to be to remove the exhaust test port located ahead of the converter to see if the problem is resolved with the test port open.

Please, if anyone can help with this I'd be grateful. I really like the car and would like to see it on the road again.

Thank you







USERNAME
Use "claim to be" below if you don't want to log in.
PASSWORD
I don't have an account. Sign me up.
CLAIM TO BE
Use only if you don't want to login (post anonymously).
ENTER CAPTCHA CODE
This is required for posting anonymously.
OPTIONS notify by email
Available only to user accounts.
SUBJECT
MODEL/YEAR
MESSAGE

DICTIONARY
LABEL(S) +
IMAGE URL *
[IMAGE LIBRARY (UPLOAD/SELECT)]

* = Field is optional.

+ = Enter space delimited labels for this post. An example entry: 240 muffler


©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.