Cause of LOW idle? - Ford Forums

Paul_NO · 04-14-2001, 20:31

My wife's '90 Ranger (2.9 v6 EFI) is barely ldling at +/- 400rpm. It has been steadily decreasing over the last year or so. It quit having a fast idle when starting cold. All I could find is that the Throttle Position Sensor may be bad. Has anyone run into this or had the TPS go bad?

04-14-2001, 20:38

in my 94 they were telling me about how they had to change the tps and some other stuff supposdly.

but the problem that i had (94 4.0v6) was that if i spepped on the gas my truck would die down in rpms and almost stall, and if i were to give it gas past half throttle it would lose power and almost stall.

i dont remember if it had low idle tho since it was a while back.

is there a check engine light on? if there is, maybe you can pull the codes to try to find out what is wrong

04-14-2001, 20:39

just thought about this too, since it is efi, could the injectors maybe be bad or clogged, or possibly the fuel filter clogged

Paul_NO · 04-14-2001, 21:14

I will be changing the fuel filter soonbut I don't think the injectors are fouled. I changed the heads in december and examined stuff while I had it apart and the injectors looked good. I need to pull the codes though.
Thanks!

04-15-2001, 02:09

yeah, i would def take a look at the Throttle Position Sensor, and also, the egr valve could be shot.

Sweens · 04-15-2001, 09:51

Paul,

That vehicle and the Bronco II with that engine were known for fuel rail contamination after many years of use. The fuel injectors plug into the fuel rail and we've found many rails rotting on the insides. The rust flakes off and plugs or partially plugs off the injector. We usually replaced the fuel rail and injectores to fix the problem, but you may be able to get away with just the rail itself. Good Luck!

04-16-2001, 17:27

Does the truck only do it when idling or does it do it when you get on the gas also?

Paul_NO · 04-16-2001, 18:10

No, it runs fine when the gas is pressed. It is just at idle that it is very low.