rxspeed87

I ws just curious on something with my idle speed
my car before I had a tps in there( damn prev owner took it off) my car was running at a idle speed of about 450-500 is that good or bad? was running rich as hell though without the TPS

rxspeed87

^

JerryLH3

iTrader: (11)

Proper idle speed should be about 700-800 rpms. If you have the TPS in now, the idle adjust screw is on top of the intake manifold covered by a little piece of rubber.

I don't think anything would have been harmed by the low idle.

HAILERS

Just a thought. If the engine was a sorry piece of junk it could't idle at a low rpm. My train of thought is that if it will idle at 400-500 rpm its probably in pretty good condition. Just my view. Yeah,750rpm and a tps.

rxspeed87

yeah the only problem now is the car is not pulling a steady idle
it has a mind of it's own
sometimes 1k is fine others 750. sometimes it likes to bounce around

also if I hit the brakes the idle will drop to 750 if it is at a higher idle.
if I turn on the lights the idle will drop about 100-300 Rpms
this idle thing is pissing me off
any idea?

the car has 166k on it
the TPS was used but it is nice and smooth and ajdusted right the plugs are new
the car will make a small pop when letting off the throttle.
if I let off the throttle most the way but JUST touching it it will making like some kind of farting sound. that started when I put the TPS on there

any ideas guys?

Dave777

I've noticed on my 89 that the more out of adjustment the tps is the more of those "little farting noises" it makes. Kind of a "poof" or a miss sound. And mine also does is right when you start to push the throttle.

I'm still trying to figure these problems out myself but, I suspect the tps has a lot to do with it. How did you check your tps? Through the test connector or directly read for 1v off the tps connection? If it is not reading that 1 volt the ecu doesn't think it's at idle and will hunt -vary the rpm etc.

My full range sensor is shot and I'm replacing mine soon, I'll let you know if it makes any problems dissapear.

rxspeed87

didn't do the 1v test, how do you do it?
the method I did was taking off the plug and reading 1k ohms at idle
it does not backfirewhen getting on the gas jsut a small poof when I let of the gas really quick though I took off my dashpot.

the other farting noise is somethin that goes on a lot only when the gas is just being touched
prolly going to fix the TPS one more time. and maybe change my O2 when I put my header on today

doklen

i have alot of the same problems with mine, Idle drops when any load is applied, and the farting sound when pressin just barely on the gas. I've had no luck at tryin to figure the idle problem out yet, but i'm gonna keep tryin so ill let you know if i find anything out.

Dave777

I have never messed with 86-88 tps's and I'm not sure how different they are. You should still be able to check for the 1 volt with a dvm, just as a back up test.

With ignition on run a probe from tps data line to ground somewhere, should read around 1 volt. The data line voltage will vary as you turn the throttle(so if you don't know which line it is you can find it this way). You can slide the dvm probe along the wire into the back of the connector (carefully) to make a contact. Try adjusting the set screw until it reads 1 volt and see if it improves anything.

Just trying to throw some more ideas out for you, if you don't feel comfortable checking this way don't worry about it.

good luck!

HAILERS

I use the 1v method on the 86/87. Put the meter on the wire that is green and red on the plug for the tps. Leave the connector connected. It should read 1v if set right. If its above or below, just turn the tps screw whichever way to make it read 1v.Its just a three wire plug on the 86/87. A word of caution here. The car HAS to be fully warmed up to test the tps. You are dealing with a fast idle cam that is intertwined with a thermowax device. If this thermowax device is not fully warmed up then the fast idle cam is not where it should be which in turn means the tps is not where it should be. I proved this to myself by taking the water thermostat out of my car with the tps already adjusted. After taking the thermostat out the tps will not drop down to the 1v setting because the thermwax has not gotten hot enought. Just a word of some caution.