My car had the stumble problem at 3,800 rpm. I read and tried nearly everything on the topic from grounding the boost sensor to double grounding the ECU, but nothing seemed to work. I was cleaning out my engine bay a few days ago before taking my bleatch to cruise around and little and noticed that the ground strap from the back of the block to the firewall was never connected. It was in poor shape so I replaced the strap, cleaned the connections and applied a little dielectric grease. Since that I no longer have the 3,800 rpm stumble! Needless to say it was a good day for me. Just goes to show ya, double check everything.

 

Uh, doesn't that count as "check your grounds"...
It's weird, cause that wire is an auxiliary ground - the main engine ground runs from above the starter to below the driver's side strut tower.


-Ted

 

Ted-what is an "auxilary ground?, Also when you say above the starter, where exactly are referring to?

 

PICS PICS PICS
Can someone post some pics of those 2 grounds???

 

You can get to it the same way you get to the primary injectors-take the upper intake off. It should be a gang of several grounds. Since my rex is my daily beater, I haven't got the nerve to take the intake off yet. doh!