1989 244 rough idle, shakes/hesitation from stop, TPS?

johnnysaltshaker · Post by **johnnysaltshaker** » 31 May 2015, 01:56

I've never posted on a forum before and i'm not much of a mechanic but here it goes. I have a 1989 244 DL Automatic with a rough idle problem. It's mileage is unknown but probably around 280-300k. The car will often shake and die after start up, usually not in the morning, but after being driven. It also hiccups a little bit when taking off from a stop and then it smooths out at higher speeds. When stopped there is a consistent light shake that repeats every 1-2 seconds. Its great on the freeway and never dies after it gets moving. I'm getting no OBD codes, and the TPS clicks when you open the throttle. But when I did the OBD TPS sensor test the TPS idle circuit did not give me its 332 (or is it 333?) code, signaling a fault. The TPS test for full throttle did give me a code, signaling that it's functioning correctly. Is this likely the cause of my problems? Do I need a new TPS or is it possible that it only needs adjusting.

Also, I took my car to a mechanic a while back (months ago), and it looks like they left the fastener loose on the giant hose that goes into the throttle body. I could get my whole hand under it and the hose was shifting around all by itself. I didn't notice it until tonight, and I'm kind of pissed. After tightening it the car seems to drive with a bit more power and the shake is more even now, but the idle still seems a little rough. TPS still a problem? Should a worry about damage to my engine after driving around for months with the throttle intake hose (I assume that's what it's called) loose?

BTW with some help I've changed the spark plugs, wires, ignition coil, fuel and air filters and for the last few weeks I've been using 91 octave chevron gas.

93Regina · Post by **93Regina** » 31 May 2015, 20:22

johnnysaltshaker wrote:BTW with some help

Well now, Do it the Volvo Way: LH2.4 Manual, and do TPS tests.

I've been using 91 octave chevron gas.

Waste of money...

marinman · Post by **marinman** » 16 Aug 2019, 13:56

Did you ever resolve this one? Seeing something very similar on my 93 240 wagon. Thanks!

lummert · Post by **lummert** » 16 Aug 2019, 20:53

93Regina wrote: ↑31 May 2015, 20:22
johnnysaltshaker wrote:BTW with some help
Well now, Do it the Volvo Way: LH2.4 Manual, and do TPS tests.

I've been using 91 octave chevron gas.
Waste of money...

I run 87 octane in my 1988 Volvo 760 Turbo Wagon with B230FT with no issues whatsoever.

Post by **volvolugnut** » 22 Aug 2019, 12:14

My thoughts are you have a moderate sized air leak after the Mass Air Flow meter. First check both clamps on the intake air duct. Position the screws where you can best reach to turn and tighten. Check all the vacuum hoses at the ends where they tend to split where pushed over the hose nipples. Some of these hoses are under the intake manifold and are a bear to get to.
Try spraying or pouring water on the hose ends and intake manifold gaskets. The water will seal the small leaks.
Don't ignore the intake manifold gasket - it can get bad over time. Carefully check for leaks before adding any more new parts. I have been there and done that for the same shaky idle - it was manifold gasket.

Volvolugnut

Post by **volvolugnut** » 22 Aug 2019, 12:20

The loose intake hose may have sucked a little dirt, but would not have been too loose or it would not run. A little loose causes the air fuel ratio to be lean at idle and caused the shake. I don't think you hurt much. My guess is the TPS is fine.

Volvolugnut