moores93

Good Day All,
My sons pickup started giving us trouble this weekend. It cranks and is very hard to start unless he pumps the gas. Then it will start but not idle. He has to keep pumping the gas to keep the pickup running.
A little history, we bought this pickup about 1.5 years ago.
We had some minor Check Engine light stuff (distributor, plugs, wires, coil, egr valve, throttle position sensor) that we have changed and the Check Engine Light has been off for a while.

My neighbor is a Ford Mechanic and happened to be by on Christmas day.
We started the pickup up and with no Air Cleaner on, watched the Throttle body. He believes it is dumping way to much fuel in there.

I am not sure.

I am off tomorrow and plan to start troubleshooting with my son.
Just wondered if any of you have any suggestions on where to start.
Thanks in advance for your help.
I hope you all had a Fantastic Christmas and Have an even better new year.

STeve

moores93

An Update for anyone with real experiene that can offer advice.
My son and I started on this yesterday and performed the following Tests per the Chiltons Manual.
Engine Coolant Temperature Sensor, passed with Flying Colors. I was amazed at how close the Temp/Resistance Values were to the book.
Throttle Positioin Sensor, Passed, .6 VDC at zero throttle, Increased slowly and steadily up to 4.5 VDC at full throttle with no noticeable hiccups.
MAP Sensor Test Key On Engine off, Chilton Says approximately .5 VDC at Sea Level. We are at almost 7000 Feet. We read 3.6 VDC. The book says it should be 4.5 VDC at Full Throttle Running. I am, based on my extremely limited experience, calling this bad. I did find another test procedure online at Part 2 -MAP Sensor Test (P0106, P0107, P0108) (GM 4.3L, 5.0L, 5.7L)
that calls for pumping the MAP sensor up to
1.) 0 in. Hg ...... 4.7 Volts.

2.) 5 in. Hg ...... 3.9 Volts.

3.) 10 in. Hg .... 3.0 Volts.

4.) 20 in. Hg .... 1.1 Volts.

My question here becomes, the obvious difference in what chiltons says, Key on Engine off, 0.5 VDC and what the website says 0 inHg, 4.7 Vots.

Any Ideas ????

moores93

FYI,
After following Chiltons and checking all of the sensors etc associated with throttle body. We gave up. Took it to a local shop that put it on a machine and determined we have NO compression on Cylinder 4 and the whole Passenger side does not run properly (likely due to cyl 4 problem)
SO,
We are trying to decide whether to put some money into it or scrap it.
Not sure what a valve job would run. most people say if you do one side, do both, do headwork etc.

Sounds like it could add up to a lot real quick.
Any input?

steve