hot start issues
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Newbie
Joined: Mar 2008
Posts: 8
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From: Marina,Ca
260e
hot start issues
Hi ...i am back for more advice.I recently replaced the ovp relay as i was having some stalling issues and i recieved the advice to do that from his forum.My newest issue however is that i have problems with a warm start.i can't tell if flooding or starving.....but it sure doesn't like the warm start.cold start is perfect,cranks right up and over.
I looked thru the book i have but i didn't find too much info abourt troubleshooting a m103 with a hot start problem.
i haven't removed the dist yet to check behind it but one of the symptoms is that when attempting to warm start it just cranks and cranks, but i never hear it fire,sometimes it will occasionally backfire thru the throttle body as if the timing is off.
i don't beleieve this is related however i will throw it in here anyway,on the powersteering,if you turn the wheel all the way one way or the other you can hear it pull the engine down and it will stall,i think this is because the power sterring filter is shot and its overfilled but man it really will lug the engine.
I looked thru the book i have but i didn't find too much info abourt troubleshooting a m103 with a hot start problem.
i haven't removed the dist yet to check behind it but one of the symptoms is that when attempting to warm start it just cranks and cranks, but i never hear it fire,sometimes it will occasionally backfire thru the throttle body as if the timing is off.
i don't beleieve this is related however i will throw it in here anyway,on the powersteering,if you turn the wheel all the way one way or the other you can hear it pull the engine down and it will stall,i think this is because the power sterring filter is shot and its overfilled but man it really will lug the engine.
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Joined: Dec 2006
Posts: 1,042
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From: Bellevue, NE
1995 E320 SE, 162,000 Miles (Sold) 2007 CLK350 Cabriolet 2014 ML550
This is a fairly common problem with the Bosch K-Jet systems used on the M103. There is a lengthy thread on here somewhere about this issue. I don't recall if it was resolved or not, but one thing that can cause this is the use of anything other than premium fuel. Lower octane fuel boils (vaporizes) at a lower temp and causes vapor locking and the engine starves for fuel during a hot start. If you are using premium, try a different brand.
Flooding is extremely unlikely unless the fuel distributor is completely shot, in which case it would run terribly all the time. A flaky temp sensor could also be at fault which would give the control unit a false reading when hot or cold. Usually that causes a cold start problem as the cold start valve fails to energize, but maybe it could cause a hot start problem as well.
Flooding is extremely unlikely unless the fuel distributor is completely shot, in which case it would run terribly all the time. A flaky temp sensor could also be at fault which would give the control unit a false reading when hot or cold. Usually that causes a cold start problem as the cold start valve fails to energize, but maybe it could cause a hot start problem as well.
Almost a Member!
Joined: Feb 2007
Posts: 34
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From: Sydney, Australia
'86 300e
theres a few things that can cause that - faulty temp sensor as mentioned by shdoug (if youre going to check it, check the right one - there are two and they do different things, the one that needs checking is the one that communicates with the ecu), also faulty fuel pump relay - I just replaced one of those even though my quite good mechanic had a look at the old one and said he thought it looked ok (you can take the cover off and check for dry solders etc) I looked at it myself and it looked fine but when i put a replacement in the car stopped cutting out on me. Also the distributor/rotor is likely to be worn out if it hasnt already been replaced - they get little cracks in them and when you get a bit of humidity they short out.
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From: REHOBOTH BEACH DE
88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
The CIS-E has a fuel accumulator located near the fuel pumps.
It should maintain about 30psi for about 30 minutes with the engine and fuel pumps off.
If it is losing pressure the result will be hot start problems and possible vapor lock.
It should maintain about 30psi for about 30 minutes with the engine and fuel pumps off.
If it is losing pressure the result will be hot start problems and possible vapor lock.
