need some help
 

This is on my brothers 95. It has an AFE stage 2, superchips, and straight pipe. He change his oil and fuel filter the other day. When he started it up the next morning it was smoking white like when the motors cold. He tried to drive but it wont go above 1500rpm before it starts missing, backfireing, and dumping lots of white smoke. When driving the smoke turn more black like you have the foot on the floor. At first I thought maybe he had broke the fuel heater, but its 100deg out and you can let the truck idle all day and it doesnt make a difference. We ran a buzz test and all sounded fine. Tried to run a contrabution test, but it kept stopping the test and giving a oil temp sensor malfunction code. The sensor worked when data logging but we replaced anyways with no luck. Could use some help getting pointed in the right direction. i was also thinking injector cups, but i would think that the truck would still rev over 1500. thanx in advance.

have you unplugged the chip yet?

Not sure if they tried that yet. I was out of town yesterday when they where jackin with it some more.

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dug into it a little more today and it looks like the fuel heater might be broke. Gonna pick one up and see if that fixes it.

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Fuel heater didnt help, and with the superchips uninstalled it wont rev past 1400rpm. Could it be a cam position sensor or map? Kinda stuck on this one and could use some help.

When the engine thinks it's cold, it changes the injection timing until it warms up. I'd get that oil temp problem taken care of before shotgunning any more parts at it.

We did change the sensor, its working, were just not able to get the oil temp hot enough for it to allow us to run the test. Im starting to lean towards a weak fuel pump, gonna put a gauge on it tonight.