high idle when hot
Discussion
Mine does this too. Haven't been able to figure out why, but one thing I did discover was that resetting the ECU with the software when it was running fast reset the idle speed back to normal.
It would soon go back to a fast idle though after a few miles driving? Maybe something to do with the adaptives maps?
Other than this the fast idle, there don't seem to be any other adverse effects of symptoms so just been living with it until the next service.
It would soon go back to a fast idle though after a few miles driving? Maybe something to do with the adaptives maps?
Other than this the fast idle, there don't seem to be any other adverse effects of symptoms so just been living with it until the next service.
I only experience ~1500rpm idle after a service (only on starting her), for about the first 40 miles or so.
After that she idles at 1000rpm when hot (this will drop to ~900rpm after 500 to 1000 miles where it stays usually until the next service)
Not sure that helps, but the service does certainly lift the rpm for a good while.
After that she idles at 1000rpm when hot (this will drop to ~900rpm after 500 to 1000 miles where it stays usually until the next service)
Not sure that helps, but the service does certainly lift the rpm for a good while.
Hmmm, well it shouldn't. In my experience you would want the car to idle at around 900-950 when hot (especially for an air conditioned car as turning this on lowers the idle slightly). When I've had my TVRs serviced I've always specified this as the idle I wanted the cars set as and my dealer also concurs with this as good practice. Of course, it will idle at a fair bit less than this when it is cold. Around 600-650ish I think.
The idle should not be especially high just becuase the car was serviced although you may find it becomes less accurate as time goes on in between servicing. I have found that popping into the dealer to have the car hooked up to the laptop after about 3000 miles is not a bad idea and keeps things running smoothly.
Hope this helps.
The idle should not be especially high just becuase the car was serviced although you may find it becomes less accurate as time goes on in between servicing. I have found that popping into the dealer to have the car hooked up to the laptop after about 3000 miles is not a bad idea and keeps things running smoothly.
Hope this helps.
If the car is ticking over at 900 rpm when cold then it sounds like it's set too high on the stop. There is no cold idle control from the ecu, so it doesn't start higher and drop as it warms up like other cars.
Dave - if the tickover comes down when you reset the adaptives and then increases again it sounds like you may have an inlet air leak to me? What are your adaptive values when the tickover is at 1500?
Dave - if the tickover comes down when you reset the adaptives and then increases again it sounds like you may have an inlet air leak to me? What are your adaptive values when the tickover is at 1500?
When cold it ticks over at the normal 700 or so rpm, then when at normal operating temps, sits at the normal 900. It's only when it's really hot from being sat in traffic that the idle speed goes up. The problem goes away as soon as you get moving again so it's pointing toward something temperature related. When it does it though, the inlet temp reading on the software is 60degC+, which is the highest value accomodated by the ECU. I must try unplugging the temp sensor to default it to 15degC to see if the issue remains.
Regards the adaptive values, not sure and it'll be a while until I can check as I've moved to the states and the car is back home....missing it lots.
Regards the adaptive values, not sure and it'll be a while until I can check as I've moved to the states and the car is back home....missing it lots.
dvs_dave said:
When cold it ticks over at the normal 700 or so rpm, then when at normal operating temps, sits at the normal 900. It's only when it's really hot from being sat in traffic that the idle speed goes up. The problem goes away as soon as you get moving again so it's pointing toward something temperature related. When it does it though, the inlet temp reading on the software is 60degC+, which is the highest value accomodated by the ECU. I must try unplugging the temp sensor to default it to 15degC to see if the issue remains.
Regards the adaptive values, not sure and it'll be a while until I can check as I've moved to the states and the car is back home....missing it lots.
I didn't read your original post properly re it happening when sitting in traffic. Maybe worth checking the inlet duct is in place from the chassis plate to airbox in case it is sucking warm air from the engine bay.Regards the adaptive values, not sure and it'll be a while until I can check as I've moved to the states and the car is back home....missing it lots.
Is the US move permanent? I would love to do a coast to coast trip in the Tuscan.
The move is permanent so the car is currently only doing minimal mileage as I've recruited (not hard 
) my old man to be on caretaker duty with it. Will get it sorted in the next few months as it's due a service.
Long term plan is to bring it over to the states but it'll involve a bit of work to do it. Namely taking the engine and gearbox out, changing the glass, lights, tyres, seat belts and brake lines to US DOT approved items, and then importing it as a kit car.
Or I could just but a Corvette........
) my old man to be on caretaker duty with it. Will get it sorted in the next few months as it's due a service.Long term plan is to bring it over to the states but it'll involve a bit of work to do it. Namely taking the engine and gearbox out, changing the glass, lights, tyres, seat belts and brake lines to US DOT approved items, and then importing it as a kit car.
Or I could just but a Corvette........
Robertjp said:
It really shouldnt do this.
I had this symptom and it turned out to be one of the throttle butterflies was badly set (closed completely in fact) at idle, which caused it to idle very high (circa 1500rpm).
Definitely something to check...
Hi guysI had this symptom and it turned out to be one of the throttle butterflies was badly set (closed completely in fact) at idle, which caused it to idle very high (circa 1500rpm).
Definitely something to check...
I have the same issue, I'd like to check the throttle butterflies but have never worked on my car yet. Would you be able to give me some explanation on how to do so? thank you
The car should be at high idle until the engine is at operating temp. This is usually between 150ºand 180º depending on the vehicle. The idle should then drop on its own or if reved to a high rpm. If the high idle is kicking back on it could be a choke related issue. If the choke is not open all the way it will raise the idle of the car. On cars with a/c if the compressor kicks on when stopped at an idle, the idle may raise slightly to accomidate the power use of the compressor.
The car should be at high idle until the engine is at operating temp. This is usually between 150ºand 180º depending on the vehicle. The idle should then drop on its own or if reved to a high rpm. If the high idle is kicking back on it could be a choke related issue. If the choke is not open all the way it will raise the idle of the car. On cars with a/c if the compressor kicks on when stopped at an idle, the idle may raise slightly to accomidate the power use of the compressor.
V8Vega said:
The car should be at high idle until the engine is at operating temp. This is usually between 150ºand 180º depending on the vehicle. The idle should then drop on its own or if reved to a high rpm. If the high idle is kicking back on it could be a choke related issue. If the choke is not open all the way it will raise the idle of the car. On cars with a/c if the compressor kicks on when stopped at an idle, the idle may raise slightly to accomidate the power use of the compressor.
I think you may have posted on the wrong forum? What you've said is not relevant to the specifics of the Speed Six engine.Anyway, never did get to the bottom of it (5 years ago now, yikes!). These days I only drive my Tuscan out on the open road. No London traffic nonsense. So as the issue has never reoccurred I'm no longer inclined to chase it down.
I'm guessing that it was the car's way of telling me it doesn't like to be sat in traffic for too long.
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