after the car is warmed up and driven , a few miles , shut the car off for like 1/2 hour , restart it the idle is real low almost ready to stall , if the car sits over night the idle is fine new, oem pvc, nkg plugs, good wires, new cap /rotor , cleaned maf , timing set, no cat, running 87 octine, this is on a 88 turbo a/t full time 4wd wagon, , also new fuel filter, ,thanks

Just a suggestion... and question.... You should be running premium... if your knock sensor is doing its job its probbably sensing knock and retarding the timing to compensate... but then again.. youve had the car like this for a while right with no problems so... hmmmm

yes had the car for 2 years, i was thinking about running higher octine, but it does cost more , , instead could i put something into the fuel tank ?average mpg is 23-24 city hi way 25

just bite the bullet and fill up with 92-93 for a tank or two. see how she runs.

 

fuel additives, other than those specifically designed to clean the fuel system, are bunk. seafoam, MMO, lucas fuel injector cleaner etc are good products, but they are cleaners, not octane boosters or any other sort of snake oil type product.

 

besides, at 20 cents difference per gallon, thats only a difference of 3.20 a tank.. (16 gallons) how much could a bottle of additive cost?

 

i know it sucks, ive run lo test in all my other cars but the soob wouldnt stop pinging on low test (mines non turbo) so I had to switch.

 

give it a shot, as an experiment it certinaly cant hurt anything, and for an extra six bucks for two full tankfuls, i would say its not that expensive a diagnostic myself.

ok, i'll telll the wife , but she's pretty tight with a dollar thanks

Octane has little-to-nothing to do with idle quality. You could run 15-20 octane fuel and your car would probably idle better. High octane is a waste unless it is needed, and not needed if your car is not pinging excessively. If your car starts to ping on 87, so what; the ECU retards timing a bit and you keep going. I doubt that your sweet wife is lead-footing the car.

 

What you didn't mention is if the idle quality ever returns after a hot-start. And if you don't do a shutdown and hot-start does the idle quality degrade?

 

My guess is that it has the infamous CTS (coolant thermosensor) problem, with either a bad connection at the CTS connector or corroded wires in the wire harness above the connector.

Octane has little-to-nothing to do with idle quality. You could run 15-20 octane fuel and your car would probably idle better. High octane is a waste unless it is needed, and not needed if your car is not pinging excessively. If your car starts to ping on 87, so what; the ECU retards timing a bit and you keep going. I doubt that your sweet wife is lead-footing the car.

 

What you didn't mention is if the idle quality ever returns after a hot-start. And if you don't do a shutdown and hot-start does the idle quality degrade?

 

My guess is that it has the infamous CTS (coolant thermosensor) problem, with either a bad connection at the CTS connector or corroded wires in the wire harness above the connector.

Wait.... my car is having problems idleing too... so could the sensor be bad on my rig as well? it idles at around 1100 after its warm but when i fire it up it goes to as much as 1800

Wait.... my car is having problems idleing too... so could the sensor be bad on my rig as well? it idles at around 1100 after its warm but when i fire it up it goes to as much as 1800

Is that 1800rpm at cold idle? Does not sound too far out of whack, though that 1100 warm idle sounds too high. Could be CTS, could be sticky IAC (Idle Air Control) valve. CTS issues seem to be common on the EA82Ts, though the sensor itself does not seem to fail often (based on comments by others).

1800 is at cold idle.... it makes sense but i thought its supposed to be at around 800 rpm warm???