1995 ranger 4.0 studdering plz HELP

[95ranger]

hi my name is shaun and i hardly ever post but i do look at the site few days a week. now heres my problem my truck is a 1995 ford ranger with the 4.0 and its auto . i have replaced tons of parts on this truck tons . as of last i have been having this problem were at idle and around 1500-2000 Rpm it shutters ,stumbles a good friend of mine is a trained macanic [sorry for spelling its why i dont post lol] and he has all the fancy tools from snap on and what not .so we checked vacum and the EGR and the IAC and the MAS i just had plugs wires and fuel filter changed we cleaned the throtal body i just did plugs and wires ,new air filter cleaned TPS i just had upper and lowwer intakes gaskets done were checked to see if it had good spark and we can smell the fuel so thats not it we are stumped and every shop near me wants $80 a hour to look at it and the said it could take the whole day thats over $600 for 8hrs just to find the problem not even fix it i dont have the money for this and no were to really take it apart and look as it is cold .i really need help with this i have more money in to the truck then i paid for it at this point and trade in is like $900 not worth it to me ill keep it but i really need help finding this gremlin .any help would be apreated im in western mass if anyones close and could help or fix it for good price i know theres tons of these posts but none have the problems mine has .THANKS for any help givin

 

[Nhaz]

So you have replaced Lots of stuff without fixing the problem.

What you need to do is try to isolate where the problem is.

Start with the IAC. I don't mean replace it. I mean when you have the truck idleing at 2000 rpm Unplug the IAC. If the idle drops down to something like normal you have narrowed the problem down some.

Assuming the idle drops. The computer is telling the IAC to stay on, why is the harder question.

At this point it COULD repeat COULD be the Temp sensor. there are two temp sensors I believe, one for the gauge in the truck and the Other is for the computer.

If the idle doesn't drop then plug the iac back in and unplug the MAF sensor. if the idle drops I would suspect a MAF sensor in need of cleaning or its just bad. apparently you can get them brand new bad.

 

[95ranger]

thanks for the help but i think u missunderstud what i was saying it does not idle up to 2000 it shuders when i drive it and the rpms are at 1500-2000 it also shudders at idle but the rpm s are good and dont fluctuate at idle

 

[xdoomx]

SOunds like timing possibly? Or skipped a tooth on the timing chain?