questions about hesitation
Discussion
I just met a gentleman and he has the most gorgeous `72, 280SE, but he has some issues with it. It has the mechanically injected 6cyl engine. He has replaced the timing chain and the distributor, both have helped but not cured the problem. The problem is when the car accelerates, from a stop, the car seems to lack power and hesitates. After the engine gains a few RPM’s, it seems to catch and accelerate normally.
To me it sounds as if the mixture is a bit lean, but he has assured me that they have taken it to several European mechanic shops (I’m in the US) and that this is the best that they can get it to run.
Do any of you have any knowledge of this kind of problem or any suggestions as to a fix? He is prepared to send it to the salvage yard if he cannot get it solved.
To me it sounds as if the mixture is a bit lean, but he has assured me that they have taken it to several European mechanic shops (I’m in the US) and that this is the best that they can get it to run.
Do any of you have any knowledge of this kind of problem or any suggestions as to a fix? He is prepared to send it to the salvage yard if he cannot get it solved.
On a car that old I would suspect that something is carboned up, perhaps the EGR is stuck partially open?
Could be a vacuum leak that has been missed like the intake manifold gasket. You say it's mechanical fuel injection; injector(s) may be warn out, if it's K-Jetonic continuous injection the air metering plate may be warn out or not adjusted properly. These are just best guesses, with problems like hesitation a 5 gas emmisions test will tell a mechanic what is going on, combustion wise.
From Phoenix.
Could be a vacuum leak that has been missed like the intake manifold gasket. You say it's mechanical fuel injection; injector(s) may be warn out, if it's K-Jetonic continuous injection the air metering plate may be warn out or not adjusted properly. These are just best guesses, with problems like hesitation a 5 gas emmisions test will tell a mechanic what is going on, combustion wise.
From Phoenix.Trooper2 said:
a 5 gas emmisions test will tell a mechanic what is going on, combustion wise.
Trooper2:
The owner has had it tested and adjusted with a gas analyzer, but the problem was worse than when he took it to the mechanic.
You say a worn injector. How would you test for this?
A vacuum leak is easy to find.
An EGR leak (ie. partially open) is another good idea.
Thanks, and I will pass on all the info.
From Kansas. The injectors will need to be taken out and bench tested. If he dosen't have an old German car garage close by that might have a test bench for mechanicals, then a garage that works on Diesels might be able to help.
Has He tried Chevron Techron injector cleaner (or similar) yet to see if it improved at all?
Has He tried Chevron Techron injector cleaner (or similar) yet to see if it improved at all?
Gassing Station | Mercedes | Top of Page | What's New | My Stuff