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Topic: Please Help (Read 961 times) previous topic - next topic

Please Help

This summer i switched my 88 XR7 5.0L motor with a 93 HO mustang motor.  I had the heads ported and I got a better cam.  I thought that i had a problem with my transmission cause when it switched into third and i started coasting between 45-60 Km/Hr  it feels like the transmission was dropping down a gear and then kicking back in.  I went to the transmisson shop and he said that the transmission works fine and that it is a motor problem. The engine also idles up and down sometimes and will even quit sometimes.  I used all the parts off my old motor and transmission the only thing that is out of the mustang is the motor.  I bought the mass air conversion kit.  I was just wondering if anyone has any ideas what my problem could be.  Any help would be greatly appreciated. Thanks.

Reg

Please Help

Reply #1 –
Okay, just to cover some bases.
1. The shifting issue...
The transmission itself is probably okay but what about the Throttle Valve cable. If it is not properly adjusted, it will cause weird shifts.

2. The stalling issue...
could be a number of things but here are a couple quick things you can check.
-TPS properly set to about .98 volts
-IAC clean and not gummed up <- caused most of my stalling issues
-Split/ broken vacuum lines

Just give it a look to see whats up and you can always scan it to see if the computer is throwing any codes. That will also help lead you in the direction of the problem.

Just to clarify too. You did switch to the Mustang Computer correct? As well as changing to the 19lb injectors from the Mustang? As well as the intake manifold and throttle body and spacer? And rearranged your plug wires for the HO firing order?

Please Help

Reply #2 –
I used the motor out of a mustang so the injectors and everything would be the 19 and i did change the spark plugs around to get the right firing order.  The transmission shop adjusted the transmission cable.  I got a new computer with the mass air conversion kit that i bought.

Please Help

Reply #3 –
It sounds like you didn't change to a Mustang computer when you put the HO in. That would be your problem then.

Or if you put that '93 Mustang computer in, you need to do the mass air conversion.

If you go ahead now and do the mass air conversion and install the mass air computer, or if you already have the computer installed, complete the conversion and you should be as good as gold.

Hope that makes sense. I'm beginning to confuse myself...

Please Help

Reply #4 –
I bought the mass air kit and install it with the motor. So that aint the problem.
 

Please Help

Reply #5 –
I'm sorry, so you already have the car converted, mass air computer installed and everything.

Did you switch the the pin locations on your harness at the computer?
#51 to #38 and #11 to #32?

I'm just reaching for anything.
Your best bet is to probably scan it for codes to direct you to the problem.