fonetico

I'm plagued by fast idle (900/1000 rpm) and a fuel gauge that remains on max. Both problems appeared around the same time.

I've had an inlet refresh with new ISV and vacuum lines and replaced the fuel tank sender. No improvement.

After I replaced the sender on a 1/3 tank, the gauge appeared to work until I filled the tank. The gauge moved to max and there it remains.

With the dash setting on remaining miles, the number hovers arbitrarily up and down around 270 miles, irrespective of what's in the tank and how far I've driven. All the other indicators seem to be working normally, including miles driven which I rely on to know when to refill.

I understand the dash instruments rely on info from the ECU, specifically the EZK. I believe it also has a role in controlling idle speed.

I've recently had the LH repaired by John Speake and wonder whether it's time to talk to him again.

Any advice would be appreciated.

John Speake

LH controls idle speed, it is a closed loop system. The usual reason for a high idle is an intake vacuum leak. Have you measured vac on the front fuel damper at warm idle and what was the result ?

Ducman82

fuel gauge is a totally separate system. check your grounds, and the pod connections.

fonetico

John,
Paul Anderson did the refresh so I have to assume he checked for vacuum leaks. Could it be the MAF? I've planned on disconnecting it next to see what that reveals.

Boobman,
I've had the pod out and re-soldered most of the connections. Even tried another pod but no joy.
Am I wrong in assuming there is sharing of info between the fuel gauge and the remaining miles indicator? They seem to interact. Do they rely only on the tank sender for info?

PorKen

High idle may be due to a bad idle switch (or wiring). Check for ground at the ECU connectors (LH pin 2, EZ pin 8).

Ducman82

the signal from the fuel gauge is shared to the "miles remaining" indicator, but that indicator does not control the gauge. so new sender and still did not work right? how do the connectors look at the tank? any corrosion inside the plastic cap?

fonetico

In fact I had thought about the ECU. It was a challenge to reinstall it and maybe the connectors aren't sitting securely.

Thanks for the suggestions.

Taguid

I had a high idle after warm-up problem and I had an air leak at the intake because when the coolant crossover is removed it needs to be pushed away from the passenger side forward for the intake to clear and seal properly. I had to remove and re-install 3 times before getting a proper seal. I also replaced the Temp II sensor at the same time because it can also be a cause of high idle. I hope this helps.

fonetico

Tracy,
Yeah, I have found seating the intake a bit of a challenge but I think I've worked it out now.
I've replaced the Temp II sensor. When I start the car cold, it surges to 1200 rpm and then settles to 900/1000 rpm as it warms up. I assume this means the sensor is working.

John,
I removed the vacuum hose from the front fuel damper while the engine's idling and it has no effect. Does this mean anything? I don't have a pressure gauge but if I put my finger over the end of the hose the suction seems rather weak. How strong should it be?

As far as the fuel gauge is concerned, I tried the bleeding' obvious and disconnected the battery. Seems to be working normally now. Makes you wonder!

John Speake

You can use a cheap Gunson or similar gauge and should measure about 19 in Hg at warm idle. Much less and there is a leak.

fonetico

So John, my newly acquired Gunson tells me the pressure is 21 Hg at warm idle.
Does this mean my next step is to send you the MAF?