frankinstyn

Hello everyone. I have been posting fairly often and doing my best to help out but I've run into a quirk I can't diagnose.
I've recently taken my car in for a replacement right axle and it came out with a rough idle. It idles smooth as ever in neutral and park but when I place it in gear I get a decent vibration. Any ideas?

No engine light
No loss in gas mileage or acceleration
2.8 auto
Avant
Changed the oil immediately with no effect... 5-30w synthetic.

2.7Lturbo

didnt put the axle in right? idle/park = no spinning axles..... thats my first guess

frankinstyn

I'm not sure what you're saying. The vibration is only when I'm not moving so I thought I could rule out the axle installation. Like you said, no spinning axles when in gear but not moving.

Just to be clear this is what he replaced.

Redneck Truck

what rpm are you idling at? no misfire codes? variable intake manifold valves in correct position? fuel pressure good? no vacuum leaks?

frankinstyn

I'm idleing at 720 give or take 10

No codes whatsoever. No pending codes either

I cannot confirm what position the variable intake manifold valves are in but the linkage is in excellent shape. I'll see if its actuating if I can reach it.

I would imagine fuel pressure is good as there are no codes and I can accellerate full throttle up to over 90 with absolutely no hesitation

No vacuum leaks I can find. I replaced the vacuum lines about 6 months ago and there are no surges from the engine when I spray carb cleaner around each connection.

That I will re-verify when I check the manifold valves positions.

Thanks for the run down. I'd completely forgotten about the intake valves.

frankinstyn

I can give you a quick history if that helps.

I personally replaced the timing belt (with a proper kit) at 94,000 miles.

I personally replaced the radiator about a month later.

I replaced the timing belt kit completely again when the new thermostat failed a couple months later.

replaced the coolant reservoir...old one was seeping and yellowed.

Replaced the coolant temp sensor at 110,000 miles...preventative measure

I replaced the timing belt kit completely again (blau...what ever the name it is kit) when the new water pump bearings went bad and ruined the seal...now at 120,000 miles.

Replaced the right front axle myself at 122,000 miles due to a torn cv boot.

Replaced both tie rod ends myself at 125,000 miles when I put on new wheels. Both were completely shot.

Replaced the air box relief valve, air distribution hose, vacuum pump, fuel filler cap, and valve cover cap at 130,000 miles

Drove it across country at 145,000 miles washington to virginia...no issues

Replaced bypass coolant hose at 150,000 miles

Replaced guage cluster to fix lcd problem at 154,000 miles

Replaced valve cover...twice to fix leaks. Then realized the leaks were from the cam plugs...replaced those too. No leaks now. 156,000 miles

I had someone else (for the first time since I've owned the car) replace a part. The left front axle.

I'm now at 160,000 miles.


I hope that helps.


I don't think the axle has anything to do with it. I think he tweaked the computer a bit. Just recently it hit 17 degrees here and fried my air bag module. The mechanic mentioned that he couldn't clear it when he returned the car and now I'm thinking he may have tweaked with the computer settings somehow.

Before I had the transmission in 032 mode and had lemmiwinked the torque converter to produce more torque at idle as well as upping the limiter...could only hit 138mph on the way to Virginia.

My thoughts as with the computer settings but I want to verify there arn't any real problems before I drive it back to Washington in a month.

Redneck Truck

Posting from my phone and threaded view doesn't seem to work so if this doesn't make sense I apologize.

Make sure the babes move fully and freely through entire range of motion. If memory serves me, vacuum actuators should be pulled all the way in at idle.

Only other things I can think of are o2

Redneck Truck

Posting from my phone and threaded view doesn't seem to work so if this doesn't make sense I apologize.

Make sure the babes move fully and freely through entire range of motion. If memory serves me, vacuum actuators should be pulled all the way in at idle.

Only other things I can think of are o2 and MAF.

frankinstyn

hmmm...I was hoping to avoid the MAF.

I forgot to mention that I replaced the front O2 sensors at about 135,000 miles.

I'll go out it about 20 minutes and check out the vacuum lines for leaks those valves for proper position.

Redneck Truck

Another thing that will give you a funny idle is ccv issues and leaks. For proof, pull your oil cap off and watch the idle go to hell. I don't believe this sets a code, either. The same should hold for any related crankcase hoses.