Power Loss on Acceleration at higher RPMs

Power Loss on Acceleration at higher RPMs

Postby hankheat [OP] » September 30th 2020, 2:53pm

I'm getting power loss with acceleration at higher rpms. I've only owned this van a few weeks. It has 117k on it and was supposedly in perfect working condition & well cared for. Tho it seems like it hadnt been driven regularly in a while.
I threw in some Lucas oil and emptied a can of cleaner into the throttle body for starters. The air filter looks fine. Planning on swapping out the fuel filter but the one on there now does look pretty new. Started looking at the fuel/air side first but I know spark, exhaust, & sensors could also maybe be the issue. The oil smells slightly of gas.
It is throwing no codes.
The van starts & drives normally but will choke and lurch (but not stall) if you accelerate quickly but again it seems only at higher speeds/rpms. If you drive smoothly you might not even notice it/cause it to happen.
I have the doghouse off and I'm ready to get into it, and I'd love any advice on the order of operations to go thru trying to track this down, or if this sounds familiar.
I really hope its something easier than the fuel pump.

Other known issues: I'm losing coolant at decent rate but have yet to see a puddle. (Will be using dye to track that down next.) The ABS & Parking light do come on intermittently indicating that problem with the ECBM Ive heard tell of.
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Re: Power Loss on Acceleration at higher RPMs

Postby chevymaher » September 30th 2020, 7:21pm

Throttle body needs cleaned. Look into fuel pressure and replace the fuel filter.
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Re: Power Loss on Acceleration at higher RPMs

Postby Leeann_93Leeann_93 is online! » September 30th 2020, 10:38pm

And do a tune up - cap, rotor, plugs, wires, coil - and clean the throttle body thoroughly. That means top and bottom of the throttle blade and the bore. Usually easier to remove the throttle body from the upper manifold, but you need a new gasket if you do. While you're there, clean the IAC and its bore as well.
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Re: Power Loss on Acceleration at higher RPMs

Postby hankheat [OP] » October 1st 2020, 1:33am

Thanks y'all. So I tested fuel pressure it was normal (55-60psi). Fuel filter, yes. Yeah I will take off the throttle body to clean it more thoroughly (but not sure its gummed enough to be the sole problem.) Is it safe to rule out the fuel side of the equation?
Tomorrow I'll give a go at the electrical/spark side as suggested.
I also checked the IAT, it was fine.
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Re: Power Loss on Acceleration at higher RPMs

Postby AstroWill » October 1st 2020, 5:18pm

Check for pancake distributor disease while you are in there. Pull a front o2 sensor and see if that makes any difference.

Before adding dye, I would borrow a pressure tester from your LAPS and apply pressure to your cooling system and see if you can find the leak.
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