Hello all,

2.0L Zetec on ITB's running Megasquirt. Starts from cold and settles into a lovely idle. Drives perfectly with no issues. Only issue is when you stop for a short time say for a swiftish pint!! Car will then start first time but you have to keep it running with the throttle for a few mins then it will settle back into an idle and be fine again.

Been like it since I built it and not really a ball breaker but something I would like to sort.

I have been advised to move the air temp sensor as it's mounted on the air filter backing plate and could be getting heat soak from engine when off and reading unrealistically high on re-start therefore less fuel. I'm not convinced by this theory but it's simple enough to move so will try it this weekend.

Anyone had the same or got any pointers?

Thanks,

Matt

Sounds like an air temp sensor issue..

You could try a little more after start enrichment, or lengthen the ASE taper

A leaky fuel pressure regulator diaphrgam is another possible cause, if it is leaky if you disconnect the vac line at the regulator you should be able to smell it.

+1 for heat soak. Have you got a cold air feed/ exposed intake?

quote:

---

Originally posted by HowardB
+1 for heat soak. Have you got a cold air feed/ exposed intake?

---

Try plugging the laptop in before you try an re-start. That will give you an idea if its a heat soak issue.

+2 for heat soak into the air temp. sensor.

Had exactly the same problem with my itb setup at one point. Fortunately had an afr gauge fitted at the time, this was showing seriously weak when the issue arose and pointed me in the right direction straight away. Moved the air temp sensor to a more sheltered (from engine heat) position and problem was solved.

[Edited on 5/3/16 by GeoffT]

Thanks for the replies

Quick update.......
Moved air temp sensor out of air box.......just temp tie wrapped to brake fluid reservoir and it solved problem with re-start completely😁😁
Thanks to all....
Matt