I got my car back today after a 3.8 V6 salvage engine was installed and all is well except for one problem. When idling in Park, if you tap the brake, the tach jumps about 500 RPM (the motor does not, just the tach) and most of the idiot lights come on dimly. The donor motor came from a 2000 and my car is a 1997. Any ideas?

 

Talk to the installer -- was the job warrantied for labor?

 

Check the ground wires going to the motor as well as the other grounds if it is not a warranty with the install.

 

yep make sure all your ground wires are connected and tight. the brake switch must be searching for a ground and is using the dash/gages ground somehow. at least that what it sounds like.

 

There are a lot of grounds on the engine block including the one for the ABS system. I think it runs to the inside of the frame on the drivers side about 10 inchs in before the radiator.

 

I took it back to the shop today. It does it in Park and Nuetral. It's not doing it while in gear. We checked the ground that Gorn was referring to, but it was fine. You can hear a pop through the speakers when you tap the brake in park as well. WTF. I'm dropping the car off Saturday morning and they're going to try to figure it out. The mechanic is baffled.

 

I agree with the grounds. There is a reason that most of the electrical world is Theory and not law. We just cant explain why thing do what they do.

Massey

 

Might be a spark issue. Check your coil packs and spark plugs.

 

sounds like a ground issue to me. we had a car at work that had body work done and a replaced trans (09 corrolla) and it ran well for a few months, then started doing goofy stuff, then quit altogether. the master tech "checked the grounds" with a multimeter and found no issue, even though i did. a senior tech came over and used a test light and was getting a pulsing light. after about 20 hours of work, the master tech decided to unbolt the ground wire and found it was painted while the trans was out of the car. needless to say, anything weird going on is going to be a ground issue

 

I got my car back today and guess what the problem was? You guys already knew it was a loose ground. It was near the heads. The mechanic had to put it on the lift to get to it. I didn't see it for myself, but the issue is fixed.


Now I just need to find an AC delete pulley for a 3.8. My AC never worked and now the clutch on the compresor is clicking. Anybody recommend a specific brand?