mpfi swap: Goes straight to redline even after switch tps wires

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AH91

New Member
Got my motor to start after a very long mpfi swap, i switched the two wires at the tps and the motor then goes the redline around 3k rpms. need any knowledgeable help as soon as possible thanks!
 
sorry,
i just finished this swap
couldn't get it to start, changed the main relay and gave it some starting fluid and started right up
i burned off all the starting fluid and starts now
it will idle(1k) for a few seconds and then goes from 1k to 3k rpm in a second
i switched the tps wires around three times and still redlines at idle.
 
Redlines at idle? Are you saying the ECU is putting the motor in a limp mode and it won't rev past 3k rpm?

CEL? Double checked your wiring with a schematic?
 
Im getting all kinds of codes im going to find them out, i dont think my ecu is in limp mode, my car does not idle at 1k rpm like It should, it idles at redline or at 3k rpm, does that make enough sense?
 
I'm really confused by your descriptions.
 
From what I've somewhat deciphered from your horrible descriptions, it sounds to me like you've got a vacuum leak. That'll let more air into the motor than the throttle is metering, and cause it to idle crazy high. Make sure you don't have any vacuum ports on the intake manifold open, and make sure you don't have any broken vacuum lines or hoses. You can take a can of BrakeClean (make sure it's the flammable stuff, they sell non-flammable that will NOT work for this) and spray it all over the intake manifold and top of the motor, and if the BrakeClean hits the spot where you've got a vacuum leak it'll cause the rpm to jump up even higher.

It could be something as simple as an injector not seated all the way, a bad injector seal, loose throttle body, loose MAP sensor, loose IACV...
 
First of all Year/make/Model sounds like you did a MPFI conversion make sure you have the injectors in the correct order running a resistor box if you are using the OBD-0 peak & hold injectors. Check and make sure you have power going to your IACV black/yellow stripe wire if not you need to get power to that wire. Could be that you have the CYP wires reversed or your Crank angle wires reversed double check them.
 
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