i am having the same type problem with my 1985 500 SEC USA version. I can be driving with my foot on the gas and the car will lose power and go dead. then it is hard to start but if i let it sit for about a minute it will re-start with ease what do i need to do to fix it

i am having the same type problem with my 1985 500 SEC USA version. I can be driving with my foot on the gas and the car will lose power and go dead. then it is hard to start but if i let it sit for about a minute it will re-start with ease what do i need to do to fix it

most likely the problem

I am having similiar issues with my 1991 300 sl . Morning starts are normal, after sitting for ten minutes to 1 hour the engine stumbles to life, after sitting outside in the hot sun ( 75-80 degrees ) this is my worst condition , it will sometimes require several attempts to get started,starts after short shut downs such as refueling are normal. Can flooding from leaking injectors be a problem after 8 or 9 hours if the vehicle is sitting in the hot sun??I was thinking about pulling spark plugs to see if they are fuel soaked to verify flooding ... any thoughts? Thanks dan

Also was thinking about coolant temp sensor being faulty...normal start after sitting over night (cool temps) difficult starts after warmed to normal operating temps and allowed to sit but not cool to stone cold . Any ideas? Thanks, Dan

Did you ever consider the OVP relay?????

NOTORIOUS for crap like that-

Overage Voltage Protection relay

Is there a reliable way to test the OVP relay???

Does a 1991 300sl have an OVP if so where is it located? Dan

Stargazer, well how did you do?what where the results of your changes and did you do one at a time so we would gain the info needed for others?JNT

Hey just-n.... i haven't had a chance to do it yet .... I just ordered some injector seals -- and will have it this week - then planning to do it this weekend ..also it is 40 - so am waiting for warmer weather also...

I also bought a fuel filter , fuel accumulator and OVP etc -- just to be sure!!

Update. Well I changed out five of the 6 injectors, and the stumbling start is basically the same. Although the car had been running plenty smooth, it runs even smoother now. The last injector is the one right by the cold start valve so I'll change it with the cold start valve. There are also some air hoses there and I just know they'll break if disturbed. I also tried a new fuel pump relay, which powers the cold start valve but again no change to the start. So that leaves me with the cold start valve as the last item to change. I'll throw in the towel after that.

glenmore
1991 300CE
2000 C280
1990 LS400

I will be doing the same thing tomorrow. Any tips on do's and don'ts would be appreciated. Am also prepared to change the rubber underneath the cold start valve, which also connects to the ICV. That will be the real challenge but have read some tips to deal with it.

Am hoping all these work will be worthwhile. What I am trying to corrrect is the false start to my 89 300e which I suspect to have leaky fuel injectors.

__________________
joel

Prayers bring forth enlightenment.

5 of the 6 injectors have pretty good access. I did most with a regular allen wrench but a short stubby would have been handy or best would be a ball allen. You can probably reuse the insulators but might as well change them and you'll need both new insulator O rings and new injector seals. Flare wrenches are handy. I also just changed the fuel filter. The insulators with new O rings are a tight fit. I tapped them in with a 15mm socket. Oil liberally around the new O ring with fresh oil. Take care when pulling out the old insulator. There will be a lot of dirt and grit there stopped by the O ring. Liberally oil the shaft of the new injector before you press it into the new seal. What I did was to hold the new insulator, insert the new seal into the insulator, oil up the new injector and press it in. Make sure the injector is correctly seated into the seal and then pull it and the injector back out of the insulator. Put the new O ring on the insulator and press into the block and then plug in your new injector w/seal.

I bought a new cold start valve gasket. It is just a piece of stiff paper.

The new injectors did not fix my stumble start but the car does run even smoother and throttle response seems to be crisper.

If you have and tips concerning the cold start valve, let me know. That is my next step.

Thanks,

glenmore
1991 300CE
2000 C280
1990 LS400

Thats a lot of parts!

I'm pretty sure the your problem is related to either the fuel distributor or the black Bosch EHA valve mounted on it or BOTH.

Try to disconnect the EHA the start the car after 10 minutes to see whether it starts or not. If it started that doesn't mean that the EHA is bad but it could be the fuel distributor.

__________________
Master Computer Engineer, A+, Network+, MCP/MCSA/MCSE 4/2k/2k3 - Messaging, MCTS, MCITP, MCT, Brainbench, ICDL and starting Ph.D

380SE 1984 <------- Totaled by flipping accident
300SE 1988 <------- Sold
Volvo S70 2000 <---- 4 family
Opel Omega 2002 <-- 4 family
560SEC 1989 <------ Sold
560SEL 1990 <------ Sold
560SEL 1991 <------ 4 my mother
560SEL 1989 <------ Sold
600SEL 1992 <------ Current

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