Where to look next? Feedback/advice?

[spacecad3t]

What happens if you disconnect the TPS?

I'll go out and check soon, what should it do?

[Tom]

What happens if you disconnect the TPS?

I'll go out and check soon, what should it do?

Just looking for clues to see if it's just getting too much air or if the system is just letting it run fast. If it jumps up further, that would suggest the system is 'trying' to bring the rpms down to idle speed. If it stays the same, then I'd want to check the idle contact again...

[spacecad3t]

What happens if you disconnect the TPS?

I'll go out and check soon, what should it do?

Just looking for clues to see if it's just getting too much air or if the system is just letting it run fast. If it jumps up further, that would suggest the system is 'trying' to bring the rpms down to idle speed. If it stays the same, then I'd want to check the idle contact again...

Ok, thanks Tom. Ill report back.

It seems so dead simple, I cleaned the matting surfaces, had 3 brand new o-rings, all fit and looked the same, so just picked one. The bolts all threaded nicely, feel very tight.

[spacecad3t]

Updates...

- Disconnected TPS, idle goes higher, 1800.
- Disconnected ICV, no change.
- Open the bypass screw, eventually causes the car to surge very badly. This never happened before actually... I could open the bypass alot and it would just rev.
- I pulled the TB again... Seal does not look pinched, no bolts were loose. (photo)
- I swapped to another TPS that I have. No change, 1400 idle.
- Put a vac gauge on it... 18-19

Somehow I introduced a-lot air since changing my o-ring.

[Tom]

Updates...

- Disconnected TPS, idle goes higher, 1800.
- Disconnected ICV, no change.
- Open the bypass screw, eventually causes the car to surge very badly. This never happened before actually... I could open the bypass alot and it would just rev.
- I pulled the TB again... Seal does not look pinched, no bolts were loose. (photo)
- I swapped to another TPS that I have. No change, 1400 idle.
- Put a vac gauge on it... 18-19

Somehow I introduced a-lot air since changing my o-ring.

That would suggest the engine management system is trying to reduce the rpms, which would suggest a leak (or bad ISV/ISV driver/ISV wiring). As a test, can you pull a hose off the ISV circuit (wherever convenient) and block both sides with your hand or a plastic baggie or the like? Or smoke test it and see if there is an external leak somewhere...

[spacecad3t]

Updates...

- Disconnected TPS, idle goes higher, 1800.
- Disconnected ICV, no change.
- Open the bypass screw, eventually causes the car to surge very badly. This never happened before actually... I could open the bypass alot and it would just rev.
- I pulled the TB again... Seal does not look pinched, no bolts were loose. (photo)
- I swapped to another TPS that I have. No change, 1400 idle.
- Put a vac gauge on it... 18-19

Somehow I introduced a-lot air since changing my o-ring.

That would suggest the engine management system is trying to reduce the rpms, which would suggest a leak (or bad ISV/ISV driver/ISV wiring). As a test, can you pull a hose off the ISV circuit (wherever convenient) and block both sides with your hand or a plastic baggie or the like? Or smoke test it and see if there is an external leak somewhere...

Ok... so I just ran outside and squeeze the ICV intake hose with some pliers and the idle came all the way down... The ICV is buzzing. Before my TB situation, I could jumper it and it seemed to change idle speed.

My ICV stuck open?

[johnb]

Updates...

- Disconnected TPS, idle goes higher, 1800.
- Disconnected ICV, no change.
- Open the bypass screw, eventually causes the car to surge very badly. This never happened before actually... I could open the bypass alot and it would just rev.
- I pulled the TB again... Seal does not look pinched, no bolts were loose. (photo)
- I swapped to another TPS that I have. No change, 1400 idle.
- Put a vac gauge on it... 18-19

Somehow I introduced a-lot air since changing my o-ring.

That would suggest the engine management system is trying to reduce the rpms, which would suggest a leak (or bad ISV/ISV driver/ISV wiring). As a test, can you pull a hose off the ISV circuit (wherever convenient) and block both sides with your hand or a plastic baggie or the like? Or smoke test it and see if there is an external leak somewhere...

Ok... so I just ran outside and squeeze the ICV intake hose with some pliers and the idle came all the way down... The ICV is buzzing. Before my TB situation, I could jumper it and it seemed to change idle speed.

My ICV stuck open?

With the engine off/key on, you should be able to feel the ICV opening and closing. If you can't reach it you can touch it with a screwdriver or something. I suppose that doesn't prove it's really opening and closing but it's a start.

You said you replaced it with a new one right?

[spacecad3t]

Ok. I unplugged the ICV and capped the connections from the Jboot.

Car barely ran! Opened the bypass 2 turns, its idling fine. Drove it around with lights, heat, radio, idling fine...

[Tom]

What is the status of the ISV? Your first post seemed to say it was new? Is it really new, or just a used spare?

[spacecad3t]

What is the status of the ISV? Your first post seemed to say it was new? Is it really new, or just a used spare?

It's a new Bosch unit. I had the manifold off in September to redo injectors, gaskets, hoses, threw that in because why not.