Cam owners I need help!

[MAC'n89Blckstng]

I have a fresh rebuilt motor with higher compression and an E303 cam. Ever since I put the new motor in the car surges like a mofo. When I first start the car will idle with a real nice lope and sounds awesome but after I drive her for a while she will not hold a steady idle. I tried unplugging the IAC and bumping up the idle screw but it still surges. I also have about 8 month old 02 sensors in it as well. What could be the problem? Oh yea it didn't have any idle problems before I put the new motor in. Its really startin to get on my nerves so any help is greatly appreciated.
Thanks,
Jesse

 

[N8Miller]

jesse,
your going to find that this is a very common problem. you could try cleaning and/or replacing some of your sensors to help it.

 

[MAC'n89Blckstng]

Does anybody think its a TPS problem?

 

[stang22]

What is the voltage range from idle to WOT? It should be between .99 and 4.50 volts. Pulled any codes? The TFI could be on it's way out the door as well. There are a number of different things it could be, you will just have to run everything out one by one.

Tim

 

[88_GT_5_oh]

clean your maf with electrical contact cleaner, clean out the IAC with carb cleaner, check the TPS voltage, should be about .98 with the key on motor off

also i had this problem with my new motor (see garage for mods), i did the above and it went away and i thought it was perfect till i went and got a dyno tune, that really cleaned up the idle

 

[87MustangGT5.0]

Wont these kind of things happen if you replace the cam in a speed density car? Although I know that is not the case with an 89....just wondering.

 

[90LX306]

want kind of maf u using? i had a c&L and the car ran like ass w/my cam, switched to pro-m and it fixed my problems. later

 

[Michael Yount]

If it still surges with the idle solenoid disconnected, I'd say you've got a wicked vacuum leak somewhere.

 

[MAC'n89Blckstng]

I checked all my vacuum connections plus its not constant, sometimes it will idle fine other times it willl surge. Im gonna try cleanin the mass air today hopefully that helps. It's been buggin the hell outta me. BTW Im runnin a stock mass air.