hot start

[SRPWR]

Ive had my Sr set up for about two years now with minamal issues. Now its giving me some problems.

1st- It wont start when Ive driven it even for a short period of time. It always starts on cold start perfectly and I even changed out the coolant temp sensor. 2nd- As this was occuring I aslo noticed my heater dosent get hot or even warm for that matter.

Could these be linked together? If so, what could be the problem? Thanks!

[Hijacker]

the heater not getting warm could be either a clog (unlikely) or a thermostat that is broken open (but you would have noticed a longer period of time to warm the motor). However, that won't keep your car from starting when hot.

I had a similar issue back during the winter where my car would start fine cold, but just crank when hot. I checked my fuel pressure and noticed it was way high and we surmised my FPR was broken, and extra fuel was being forced into the cylinders, flooding the motor out. A new stock unit solved my issue.

[SRPWR]

Another thing is if I do eventually get it started, eventhough its hot, it will idle as if its a cold start. (like 12 or 1300) then it will calm down to around 850 or 900 in a few minutes. It will puff black smoke(rich) and then drive normal. Could it have any thing to do with the JWT ECU tune?

[Hijacker]

oh. it's chipped. that would have changed my answer. ECU tunes can be finicky. I don't know how long you've had your tune, so I'll assume for as long as you've said you've been running the car fine.

Even though JWT doesn't have any kind of program to cover the tune for this long, you may wanna give their customer service a call and explain your symptoms.

ECUs go bad, and ROM tunes can sometimes cause them to fail quicker. JWT is one of the best in the country for chipping, but it's not to say that even they are infallible and didn't cause premature death. But that's the risk you take when you have someone solder your ECU.

Normally if you had eliminated mechanical problems, I would start in on electronic diagnosis, and I usually suggest trying someone else's ECU to see if yours is on its way out. Given ECU retunes, though, that's not as easy a proposition as it would be with a stock setup.

So I would check your fuel pressure first, eliminate any kind of mechanical failure and then contact JWT and explain the situation to them and see what they can advise you to do.

[doridori23]

Also some coolant temp sensors for the ECM can cause a no hot start issue as well. The sensor for the ECM is the 2 wire sensor and it is a simple ohm test when warm to ensure that it is functioning properly. I forget the value but it should be listed in the fsm.