94 E320- Hard Restarting warm- Help?
 

My 94 starts instantly when cold and has no driveability problems. What is driving me nuts is that when I attempt to restart it after it sits maybe 15 minutes or more it will either crank quite a while before firing, or it will start and immediately stall. This is spoiling an otherwise enjoyable car experience.

This car has had both the throttle actuator and the wiring harness replaced due to the famous faulty wires. The dealer replaced some sort of upper voltage control in an attempt to fix the starting problem but to no avail. Another shop couldn't even make the problem happen- which surprised me since I can't drive it without it happening. Any wisdom from you gurus?

have you been able to retrieve any codes to help with the diagnoses of this problem?

Both dealer and independent shop said no codes showed up. I'm not getting any dash lights indicating a problem either.

I just read through all of the TSB's for your car and the closest I could come to your hot starting problem was to replace the OVP, is that what you are referring to when you state the dealer replaced an upper voltage control unit?

How does it run after you finally get it started after it's hot? If it runs poorly i.e. stumbles, idles rough, misses while accelerating, etc. etc. than it could be a number of things.....I just resolved a bunch of running problems on my 95 E320 by just changing the spark plugs, they only had 21k miles on them but replacing them cleared up everything. I didn't have any codes with the bad plugs either......One of the TSB's suggests a faulty fuel pressure regulator too.

When it catches open the throttle a bit. There have been at least two active threads on this subject in the last couple of days.

duke

94 E320- Hard Start Problem- Solved!
 

Thought I'd give an update for the next guy who searches for a fix to this problem. As mentioned in original note my 124 started ok when cold, but after it warmed up it the car was hard to restart, long cranking time, stalling, etc. The Dealer replaced the OVP as seems to be the standard approach to this, however the problem remained. Based on info on this forum I put a new Fuel Pressure Regulator in the car this past weekend- Problem Solved. Car starts like new again. Cheers.

Glad you got your car fixed Uncle D, I guess those TSB's can help from time to time.