My only goal with this thread is to have a single, updated place where the location of the engine coils are shown.
1999 CL500. 106,000 miles. Bought it about 5,000 miles ago. New issue. Hesitates upon acceleration and loses power. Also loses power at highway speed (65mph) and the engine bucks and feels like it's going to shut off. While idling, it does not stay on, and eventually shuts off and the whole dash lights up. Can start it right up and drive again. This all happens *after* the engine temperature warms up to around 80. The problem became more apparent when Spring started, I'm guessing because outside temperatures became warmer.
I had a ton of codes. Cleared them to check to see which comes up first. So far I have just 1, a pending P0100 - MAF.
I have searched this forum, other forums, YouTube, Pelican Parts tutorials, restoreyourmercedes.com , and dozens of other sites on the web for weeks looking for a solution. Finally realized I'm being stubborn and not just simply asking for help.
(There are random bits here and there, but most of the threads die on the vine, like this one
http://www.benzworld.org/forums/w140-s-class/2240850-1996-s-420-rough-idle.html
And for example, this thread? From 2008, and the pictures links are dead. Trust me, I've been searching guys.
http://www.benzworld.org/forums/w140-s-class/1404924-please-identify-these-engine-pics-help.html )
So, to consolidate the answer into a specific thread (hopefully with some pictures) ...for all of those searching out there:
where are the coil packs for a w140 located?
There are 8. The procedure to test coil packs is to-- while the engine is running, remove each one and see if it affects the engine. If it does not, that is an offending coil.
There is also a method of putting a spark plug in the coil, and then touching the coil to the connector. Spark = good coil. That poster advised wearing heavy leather gloves while doing this. I won't be doing this myself... just mentioning it for information consolidation in this thread.
Have read numerous threads on people checking coils with a multimeter, with some saying that doing so works, and others saying that the method is not reliable.
The simplest method seems to be pulling the coils while the engine is running.
It is recommended to replace the coils with the Bosch brand only, which can be found on eBay, Amazon and other online places at varying prices from $50 to $150+.
Other things to check for the hesitation loss of power problem I listed above are plugs, distributor caps / wires, doing smoke tests for leaks, vacuum lines, MAF sensors, fuel pump (there are 2) and all kinds of things. Have read about people spending $1,000s, before simply doing a check on their coils, and that ended up being the problem.
Search terms so folks can find this thread:
- Change / Test / Check / Switch / Replace coils
- Replace coil packs
- Coil location W140, C140, S500, CL500
- Engine rough idle, hesitation, sputter, shut off, turn off, die, dies, shudder, shake
1999 CL500. 106,000 miles. Bought it about 5,000 miles ago. New issue. Hesitates upon acceleration and loses power. Also loses power at highway speed (65mph) and the engine bucks and feels like it's going to shut off. While idling, it does not stay on, and eventually shuts off and the whole dash lights up. Can start it right up and drive again. This all happens *after* the engine temperature warms up to around 80. The problem became more apparent when Spring started, I'm guessing because outside temperatures became warmer.
I had a ton of codes. Cleared them to check to see which comes up first. So far I have just 1, a pending P0100 - MAF.
I have searched this forum, other forums, YouTube, Pelican Parts tutorials, restoreyourmercedes.com , and dozens of other sites on the web for weeks looking for a solution. Finally realized I'm being stubborn and not just simply asking for help.
(There are random bits here and there, but most of the threads die on the vine, like this one
http://www.benzworld.org/forums/w140-s-class/2240850-1996-s-420-rough-idle.html
And for example, this thread? From 2008, and the pictures links are dead. Trust me, I've been searching guys.
http://www.benzworld.org/forums/w140-s-class/1404924-please-identify-these-engine-pics-help.html )
So, to consolidate the answer into a specific thread (hopefully with some pictures) ...for all of those searching out there:
where are the coil packs for a w140 located?
There are 8. The procedure to test coil packs is to-- while the engine is running, remove each one and see if it affects the engine. If it does not, that is an offending coil.
There is also a method of putting a spark plug in the coil, and then touching the coil to the connector. Spark = good coil. That poster advised wearing heavy leather gloves while doing this. I won't be doing this myself... just mentioning it for information consolidation in this thread.
Have read numerous threads on people checking coils with a multimeter, with some saying that doing so works, and others saying that the method is not reliable.
The simplest method seems to be pulling the coils while the engine is running.
It is recommended to replace the coils with the Bosch brand only, which can be found on eBay, Amazon and other online places at varying prices from $50 to $150+.
Other things to check for the hesitation loss of power problem I listed above are plugs, distributor caps / wires, doing smoke tests for leaks, vacuum lines, MAF sensors, fuel pump (there are 2) and all kinds of things. Have read about people spending $1,000s, before simply doing a check on their coils, and that ended up being the problem.
Search terms so folks can find this thread:
- Change / Test / Check / Switch / Replace coils
- Replace coil packs
- Coil location W140, C140, S500, CL500
- Engine rough idle, hesitation, sputter, shut off, turn off, die, dies, shudder, shake
