What could cause multiple TPS's to go bad? (S4 n/a)

NoDOHC · 12-14-2008, 12:21 AM

I don't know if the idle problem is your TPS or not, but the voltage should run about 0.6-0.9V from ground to the center pin (I forget what color it is and I have no stock s4 cars to look at anymore) when the throttle is closed.

EDIT: This is done with the TPS plugged in and the ignition switch in Run (with eingine running or not).

By the way, I would suspect a vacuum leak for the poor idle. If it is idling at 3,000 rpm, the BAC should be shut (trying to idle it down).

It really is a pity that you don't live a little closer.

need RX7 · 12-14-2008, 07:43 PM

Quote:

Originally Posted by NoDOHC

By the way, I would suspect a vacuum leak for the poor idle. If it is idling at 3,000 rpm, the BAC should be shut (trying to idle it down).

I'm pretty sure there's no vacuum leaks, I've replaced all the intake gaskets, injectors cleaned with new grommets and o-rings and replaced a bunch of vacuum lines after the rat's nest removal. I think the problem is purely electronic.

Also, I realize the first posts are kind of confusing, so the main questions is, is there anything that can cause a TPS to be out of spec if the TPS itself isn't bad? I'm pretty sure this TPS I have now is good, but I can't get it below 2k ohms closed and it always goes to 8k at WOT. One of the other TPS's I had that was 'bad' tested good at a dealership. I'm pretty stumped over here.

need RX7 · 12-15-2008, 08:32 PM

So I guess I just ended up with another bad TPS?

My5ABaby · 12-15-2008, 08:43 PM

Quote:

Originally Posted by need RX7

So I guess I just ended up with another bad TPS?

I had to replace mine a while back and went through a couple bad ones.

need RX7 · 12-15-2008, 09:01 PM

Dang. I guess I'm off to look for another...

12-14-2008, 12:21 AM	#1
NoDOHC The quest for more torque Join Date: Sep 2008 Location: Sheboygan, Wisconsin Posts: 855 Rep Power: 17	I don't know if the idle problem is your TPS or not, but the voltage should run about 0.6-0.9V from ground to the center pin (I forget what color it is and I have no stock s4 cars to look at anymore) when the throttle is closed. EDIT: This is done with the TPS plugged in and the ignition switch in Run (with eingine running or not). By the way, I would suspect a vacuum leak for the poor idle. If it is idling at 3,000 rpm, the BAC should be shut (trying to idle it down). It really is a pity that you don't live a little closer. __________________ 1986 GXL ('87 4-port NA - Haltech E8, LS2 Coils. Defined Autoworks Headers, Dual 2.5" Exhaust (Dual Superflow, dBX mufflers) 1991 Coupe (KYB AGX Shocks, Eibach lowering springs, RB exhaust, Stock and Automatic)

12-15-2008, 08:32 PM	#3
need RX7 Clean S4 Nutswinger Join Date: Mar 2008 Location: Sterling Heights, MI Posts: 485 Rep Power: 18	So I guess I just ended up with another bad TPS? __________________ -Ted -1986 Mazda RX7 Sport [DD/beater]: engine finally let go at 205k. parts car status. -1986 Mazda RX7 base [resto-mod project]: S5 n/a swap in progress.

12-15-2008, 09:01 PM	#5
need RX7 Clean S4 Nutswinger Join Date: Mar 2008 Location: Sterling Heights, MI Posts: 485 Rep Power: 18	Dang. I guess I'm off to look for another... __________________ -Ted -1986 Mazda RX7 Sport [DD/beater]: engine finally let go at 205k. parts car status. -1986 Mazda RX7 base [resto-mod project]: S5 n/a swap in progress.