Rising RPM

[Rob1234]

Help please 

I had a starter problem it turned out to be a fire wire fault. I got it sorted. The car now when I start it is running at high revs. It’s a lotus esprit turbo x180 model (carbs) Any one have any ideas? Its running around 1500 rpm the rises to 3500rmp after around 30seconds at that stage I switched it off. Thanks 

[AndyPG]

Hi Rob,

Is your throttle cable and or linkage at the carbs binding open a little?

To rev that high would suggest to me the throttle isn't returning to the idle position properly.

Have any vacuum hoses come off?

Andy.

[jonwat]

What about the throttle jack that raises the revs when the air con is on, assuming you have air con. 

[sailorbob]

A little more information would help. Is the RPM rise occurring on its own? i.e. you start the car, don't touch the throttle, and the revs rise. Also, is it happening on a cold, warm or hot start?

My initial thoughts would be to ensure the throttle cable has a little slack in it and to check for any air leaks after the carb butterflies.

[Rob1234]

On 11/02/2020 at 08:24, AndyPG said:

Hi Rob,

Is your throttle cable and or linkage at the carbs binding open a little?

To rev that high would suggest to me the throttle isn't returning to the idle position properly.

Have any vacuum hoses come off?

Andy.

Hi Andy how are you? I loosened a hose beside my starter to gain access to starter. I started the car for a few seconds when I got stater working but hadn’t the hose connected. I now the hose connected and starting cold the car rises rpm with in 30seconds or so. All other cables seem to be fine. Would the car eventually clear the intake from the hose that I had disconnected or what would I do to rectify. Really appreciate help here guys 

[Rob1234]

On 11/02/2020 at 15:35, sailorbob said:

A little more information would help. Is the RPM rise occurring on its own? i.e. you start the car, don't touch the throttle, and the revs rise. Also, is it happening on a cold, warm or hot start?

My initial thoughts would be to ensure the throttle cable has a little slack in it and to check for any air leaks after the carb butterflies.

Hi Sailorbob how are you? I loosened a hose beside my starter to gain access to starter. I started the car for a few seconds when I got stater working but hadn’t the hose connected. I now the hose connected and starting cold the car rises rpm with in 30seconds or so. All other cables seem to be fine. Would the car eventually clear the intake from the hose that I had disconnected or what would I do to rectify. Really appreciate help here guys 

 

 

[JayTwo]

I had a similar problem this summer and it turned out to be the throttle jack as @jonwat suggests.  I've just left it unplugged since, it's easy enough to get to, on the forward carb pushing a lever attached to the end of the throttle spindle.

Also found and fixed a snapped throttle return spring (between the carbs) but that didn't seem to be causing any problems strangely!

[sailorbob]

If this started after the hose was disconnected then I suspect the hose is not connected properly or it has a split. I would check that next.