Trouble starting when outside in sun or when hot. Cold start or from garage is fine.

[jrothenb]

DMC'ers - apologies since this has probably been covered on here before, but my level of mechanical knowledge probably is keeping me from knowing what keywords to search for!

My car will start just fine if it's been sitting in the garage or unused for a little while. However, if it's been sitting outside in the hot sun or has been used, getting it to start is a real hassle. It will turn over for what seems like minutes, until I'm afraid I'm about to use up the battery. It will eventually start reluctantly, but it's always scary and I'm trying to figure out what the issue is so we can resolve. I have an awesome mechanic who is going to help, but I thought maybe this community might have some ideas of where he should start looking.

Thanks for your help! Jeff

[NightFlyer]

Before I took my car out of long term storage last year, I had replaced the fuel accumulator, the fuel pump and sender with the DMCH combo unit, and the stock/OEM fuel pump and accumulator hoses with Gates fuel injection hoses. Regardless, I was still experiencing a hot start (and sometimes even a cold start) problem, which was most prevalent when I had the car parked in direct sunlight on very warm days. What solved such a problem for me was the addition of an external in-line check valve at the fuel pump:

http://dmctalk.org/showthread.php?8085-Hot-start-problem-resolved-due-to-failed-check-valve-in-the-DMCH-fuel-pump

I'm running and can highly recommend this check valve:

http://www.usplastic.com/catalog/images/products/Valves/sku/22398psku.jpg

http://www.usplastic.com/catalog/item.aspx?itemid=85394&catid=945

While this solved my problem, your problem could also be caused by the cold start valve/system flooding the engine for one of several potential reasons. You can try unplugging the CSV when experiencing the symptom and see what happens - this is also laid out within the above thread.

Absent the fuel pump check valve and a mis-functioning CSV system (several potential causes including a malfunctioning thermal time switch), general hot start problems are also frequently caused by a kinked/leaky fuel hose, a worn out fuel accumulator, or a deformed PPR o-ring.

Best of luck!

[David T]

The next time you have trouble starting it try the "Plug Swap". See if that gets it going. Depending on what happens (starting easier or not) is a big clue as to where to look next. The "Plug Swap" consists of taking the plugs off of the Cold Start Valve and the Control Pressure Regulator and switching them. Just as soon as the motor starts you must IMMEDIATELY switch them back.

[djdogbone]

This really sounds like a fuel accumulator problem. When they start to go bad. This is a common behavior.

[Flicky]

Does the car run hot? It could be you are super lean. If you can't tell, a dyno run with a wide band will tell you.
As other are saying, most likely it is the accumulator. I'd replace the fuel pump too. I can't imagine it is the stock one, but I replace everything that is not less than a year old. If that doesn't fix it I'd really examine the lines for some type of leakage.

[Jonathan]

I would suggest it is the fuel accumulator as well from what you described.

If it is original, it's not unusual for it to begin to show problems. Replacing it with a new one would be my recommendation.

You can also replace other fuel hoses, filters, fittings or whatnot at the same time, but if you are replacing items to correct a problem versus doing it proactively, I might stick to replacing just one item at a time. I.e. do the accumulator now but wait to do the fuel pump until you see whether this problem went away. Not in terms of making the overall job easier by separating it out, but to make your troubleshooting easier by knowing exactly what changed and whether the car's performance changed with it.

Fix known problems first and then move on to replacing parts or upgrading areas as part of preventive maintenance on their own.

[jrothenb]

THANK YOU for these replies so far! We now have a great idea of where to start and I'll be sure to let you know what we find out. All best!

[JohnZ]

I plan to replace my fuel accumulator too, but I'm going to do it after I'm done with the brakes... I want to take the car to my uncle's since he has the "mechanics hole in the ground" (I don't know how to say in in english!:wiggle:) in his laboratory. Sound much easier with that!

I took DPI's OEM size accumulator, though I'm not really aware of the differences between mine and the smaller version...

:D