Just did motor swap, now its cutting out???

[dnthmn87]

Hey I'm a newbie here, and have a good question about my car cutting out at 4500 rpms. I just put a 3.8L supercharged motor and trans out of a 98 oldsmobile LSS into a 99 GTP (same motor and trans). I had to change a few brackets, pulleys, and mounts etc, but didn't change the throttle body. The motor ran just fine in the olds, but now its cutting out at 4500 rpms, no check engine light. Could the PCM have trouble getting signals from a 98 MAF or any sensor in the throttle body? It has the coil pack off of the GTP motor i pulled out, which ran fine till the crank bearings took a dump, but it had 228,100 miles. Could any sensors from the 98 motor cause this since the PCM is a 99?

[01gpgt01]

Pretty sure the 98 Maf is deferent then the 99 maf. There would be your issue, Install your TB on the blower

[BillBoost37]

Maf won't cause this type of isse. Been there, proved that, done that.

I'd check for a vacuum leak and or fuel pressure for starters. Unless the piece on the transmission was different for shfiting the car into gear. (the metal arm, check that) and the pcm thinks the car is in neutral when it's in D on the shifter. Then it'll hit you with the limiter as if you were in park or neutral.

[dnthmn87]

I might just swap out the throttle body anyways, but I'm thinking fuel filter might be clogged since the GTP sat for a few months before I bought it, and who knows when they changed it last. And that that shifter rod on the tranny kinda got beat up during the swap, so I'll look at those few things, thanks.

[4boostin]

This is the Dad here.....After driving it I suggested swapping the coil packs first.....Problem fixed!!

Bill was right, the 98 MAF and TB are working fine.