i've got a problem with my motor starting it does'nt do it all the time,it could be cold or hot and it will act up but i noticed if i crank the motor a couple of times and pump the gas pedal a couple of times it would start eventually. And when it does start up the idle moves up and down from 800 to 1700 but not constant i could be driving perfectly down the road and stop at a stop light and it would happen even if i let of the gas coasting and a straight road the idle would move up and down please help me this is my only vehicle and my starter is taking a beating from cranking at long periods of time


-checked M.A.F ,cleaned
- cleaned throttle body but didn't unbolt

 

anyone ran into this problem?

 

whens the last time you did a fuel filter?

 

about 5,000 miles ago,and i have good power through all the rpm's

 

More info needed--tells us everything you can about the truck--maintenance, Auto/Manual, 2.7 or 3.4----fill the page....

But here is a truth--at about 100k you have to replace certain items like the TPS, O2's/AFR's, Timing belt, plugs and wires.......etc...

I would sweep the TPS and customary sensors and then check the Timing belt.

 

thats the thing the person i bought it from told me he changed everything at 150,000 miles now it has about 180,000 and everything looks new, it's an auto 3.4l

 

gives signs like and idle air control motor also. but not to sure on this engines.

 

how can i clean an I.A.C?

 

Have you checked all your grounds and vacuum hoses?
Also check the throttle positioning sensor as suggested up above.

 

you cant its just a r&r as far as i know. but like i said not really to sure as to were it is on these but its worth checking out. wish i was at the shop i would look it up on how to test it. but see if you can find someone with all data or something to see if it test good. does it afect it at all if you have the a/c on or not?

 

99% it's your IAC. At times a dirty MAF will keep one from wanting to idle well due to the extreme lean condition created, but they usually don't fluctuate when this happens and usually throw a code. At 180K IAC is the best bet.

 

does the IAC have anything to do with the motor not wanting to start and the only way to get the motor to run is to pump the gas pedal and crank at the same time?

 

yes it would its the idle air control motor it controls the ideal. i had a truck that would start but had to push the gas to get it to start would run good but not idle. it has every thing to do with your idle.

 

Actually, i would check your coolant level and you temperature sensor--in this case.

You can clean the IAC valve--buy some electronics cleaner and open it up. Clean out the junk if there is any and put back together using a little RTV at possible.......

I doubt it is your IAC though

I would also check the Fuel Pressure Regulator (FPR) and OHM the Fuel pump. The leads for the fuel pump can he located under the rear seats under a small plate above the gas tank.

Two things are happening--either it is too rich or too lean when it is starting. When this starts happening again--try having a friend prime the intake with a little gas or starting fluid (Go easy with starting fluid!!!)

It it kicks over with that test you know you have a fuel problem....

AND WORD OF ADVICE--DONT GUESS--CHECK

 

thanks hross14

 

checked fuel pump, tested fuel pressure, anyother suggestions anybody?

 

three items needed

Fuel
Spark Air

Then move onto Compression and timing