View Poll Results: FrankW's Obsidian Obsession
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Frank's C32 Obsidian Obsession
#1351
Super Moderator
Yeah - The POS is built on the Neon platform & man that engine resists being revved.
#1353
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white and whiter
Frank old chap - for a seasoned campaigner - It's time you had an OBDII/CAN scanner - the 32 now has some miles on her - go buy one, a nice one. The STAR can within reason diagnose a bad coilpack. You can try as mleskovar suggests - to my knowledge the 3 IN wires are 2 X power wires to the coil primaries & one return (earth). I think she fires the 2 plugs a degree or two apart for clean burn.
The problem is that compression suppresses spark - a plug will fire properly in free air but under compression can fail to fire properly through bad plug or coil or excessive wire resistance or breakdown. This on a blown engine should show up at maximum volumetric efficiency - i.e. when the supercharger is at maximum blow pressure.
You say it's bad from idle - does it get worse when you load the engine & get the revs up on the SC? Can you feel the misfire pop with hand over the exhaust? I know on a twinspark 6 this can be difficult to detect.
I don't want to add other variables to the equation & I must say the problem sounds electrical after earlier scares. When last did that engine have a CPS? The day is going to come where we must take a plug out of each cylinder & do a compression test to check for a leaking valve. If for no other reason than to eliminate the possibility. Are all the vacuum lines in good order? They can't be too bad or you would get a fuel trim warning.
Can you please backtrack - What did you do to the engine prior to this trouble starting? Did you do or change anything prior to the trouble? You were talking about O2 sensors at one time - did you change them? A bad O2 sensor can cause stumble - that's however not what you are explaining.
Have you looked at the engine compartment in the dark at night with the airbox/es off. Can you see any sparks jumping around through the wire or coil insulation anywhere?
Good luck
The problem is that compression suppresses spark - a plug will fire properly in free air but under compression can fail to fire properly through bad plug or coil or excessive wire resistance or breakdown. This on a blown engine should show up at maximum volumetric efficiency - i.e. when the supercharger is at maximum blow pressure.
You say it's bad from idle - does it get worse when you load the engine & get the revs up on the SC? Can you feel the misfire pop with hand over the exhaust? I know on a twinspark 6 this can be difficult to detect.
I don't want to add other variables to the equation & I must say the problem sounds electrical after earlier scares. When last did that engine have a CPS? The day is going to come where we must take a plug out of each cylinder & do a compression test to check for a leaking valve. If for no other reason than to eliminate the possibility. Are all the vacuum lines in good order? They can't be too bad or you would get a fuel trim warning.
Can you please backtrack - What did you do to the engine prior to this trouble starting? Did you do or change anything prior to the trouble? You were talking about O2 sensors at one time - did you change them? A bad O2 sensor can cause stumble - that's however not what you are explaining.
Have you looked at the engine compartment in the dark at night with the airbox/es off. Can you see any sparks jumping around through the wire or coil insulation anywhere?
Good luck
rough idle started when one of the wire came loose. I snapped it back. it was fine for few days and then it got worse.
everything else was checked.
the only other problem is exhaust leak on the driver side header, but I thought exhaust leak wouldn't cause bad idle.
#1356
Super Moderator
the engine under load doesn't shake. only when it comes to a stop when idling. can definitely feel and hear the irregular pulse.
rough idle started when one of the wire came loose. I snapped it back. it was fine for few days and then it got worse.
everything else was checked.
the only other problem is exhaust leak on the driver side header, but I thought exhaust leak wouldn't cause bad idle.
rough idle started when one of the wire came loose. I snapped it back. it was fine for few days and then it got worse.
everything else was checked.
the only other problem is exhaust leak on the driver side header, but I thought exhaust leak wouldn't cause bad idle.
#1359
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Midnight Blue 2004.5 C230 Kompressor Sport Sedan. 2002 w210 E320, 2009 w211 E350 Sport
the engine under load doesn't shake. only when it comes to a stop when idling. can definitely feel and hear the irregular pulse.
rough idle started when one of the wire came loose. I snapped it back. it was fine for few days and then it got worse.
everything else was checked.
the only other problem is exhaust leak on the driver side header, but I thought exhaust leak wouldn't cause bad idle.
rough idle started when one of the wire came loose. I snapped it back. it was fine for few days and then it got worse.
everything else was checked.
the only other problem is exhaust leak on the driver side header, but I thought exhaust leak wouldn't cause bad idle.
#1360
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white and whiter
also added another chevron fuel injector cleaner to this tank of gas.
going to have the code read tomorrow noon time. we'll see what goes.
on the throttle everything feels pretty normal. only when off the throttle it vibrates.
passenger bank...all plugs look great when i pull them out.
i'm leaning towards my driver side primary is f-ed or driver side 02 sensors are f-ed, but no codes showing 02 sensor fault.
OR if I'm really unlucky that the driverside ignition harness is f-ed.
we'll see.
at least under WOT the car still goes like no tomorrow.
#1361
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#1362
Super Moderator
I'm not worried about the outside - are the plug tips in the combustion chamber oily? Boroscope, compression & leakdown test required if so. You said the engine was ticking earlier. You really must check this because if you have a broken ring you need to catch it early - If you score an alusil bore it means a new block. (crankcase with bores) You Americans talk about short blocks & things - That terminology is not used anywhere else in the world.
Last edited by Glyn M Ruck; 07-10-2009 at 01:22 PM.
#1363
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white and whiter
I'm not worried about the outside - are the plug tips in the combustion chamber oily? Boroscope, compression & leakdown test required if so. You said the engine was ticking earlier. You really must check this because if you have a broken ring you need to catch it early - If you score an alusil bore it means a new block. (crankcase with bores) You Americans talk about short blocks & things - That terminology is not used anywhere else in the world.
#1364
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Midnight Blue 2004.5 C230 Kompressor Sport Sedan. 2002 w210 E320, 2009 w211 E350 Sport
either way....I eliminated the ignition wires and spark plugs as the cause today. changed out all 12 plugs. #4 and #6 which had the code the plugs were covered in oil even on the outside.
also added another chevron fuel injector cleaner to this tank of gas.
going to have the code read tomorrow noon time. we'll see what goes.
on the throttle everything feels pretty normal. only when off the throttle it vibrates.
passenger bank...all plugs look great when i pull them out.
i'm leaning towards my driver side primary is f-ed or driver side 02 sensors are f-ed, but no codes showing 02 sensor fault.
OR if I'm really unlucky that the driverside ignition harness is f-ed.
we'll see.
at least under WOT the car still goes like no tomorrow.
also added another chevron fuel injector cleaner to this tank of gas.
going to have the code read tomorrow noon time. we'll see what goes.
on the throttle everything feels pretty normal. only when off the throttle it vibrates.
passenger bank...all plugs look great when i pull them out.
i'm leaning towards my driver side primary is f-ed or driver side 02 sensors are f-ed, but no codes showing 02 sensor fault.
OR if I'm really unlucky that the driverside ignition harness is f-ed.
we'll see.
at least under WOT the car still goes like no tomorrow.
#1365
Super Moderator
Frank - Then you have a rocker gasket leak or that cursed PCV cover leak. If the plugs look OK in the combustion chamber then oil is not an internal problem plus the car would smoke if it was internal.
#1366
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white and whiter
talked to my tuner shop guy who used to be a MB tech as well. He thinks it may be the MAP or the EGS? or it could be just dirty valve.
#1369
Super Moderator
I believe it is sensor 45 in this diagram.
#1371
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#1372
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white and whiter
thanks. will need it. the new TB the dealer put in a while back now has a black rubber piece that covers the connector which makes it heck of a lot harder for me to pull the y-splitter out.
btw, I'm looking on rmeuropean for MAP part, but can't seen to find it under engine, air intake category, etc. any help is welcome.
btw, I'm looking on rmeuropean for MAP part, but can't seen to find it under engine, air intake category, etc. any help is welcome.
#1373
Super Moderator
You say it’s not down on power…maybe now’s my chance.
MAP sensor is 005 153 72 28; requires seal 027 997 27 48. Don't ask how I know.
Best wishes getting things squared away.
#1374
Super Moderator
Thanks John - I was not sure if my PN detail was up to date - seal is 50 in diag.
PNs I had were - sensor 0041533328 & seal 0279972748 - looks like yours is an updated sensor.
PNs I had were - sensor 0041533328 & seal 0279972748 - looks like yours is an updated sensor.
Last edited by Glyn M Ruck; 07-11-2009 at 08:41 PM.
#1375
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white and whiter
valve
this car just hates me more and more.
was adjusting the driver side camber and decide to move her out of the way of the pepper tree with leaves falling all over the place.
started her up and hear the loudest tapping noise I've heard ever from her. pop the hood put my ear down on all possible things (passenger bank valves, TB, driver side bank valves, purge valve) and yup...the noise is definitely coming from the driver side valves. giving it some gas and the noise speed up and gets less noisy and after about a min the noise completely went away. while there was the loud tapping the idle is rough and after the noise stopped the idle was better.
soooo on top of everything that are possible causes for the recent events this leads me to think maybe because the car wasn't firing properly for a while due to ignition wires dying and because the car is tuned to run slightly rich the misfire caused built up in the valves etc.
so far I've eliminated the wires, plugs, and possibly the coils (running two coil packs from the CLK to replace the one that was questionable. the CLK runs fine and the 32 still doing what it's doing).
next on the list are MAP, EGR, and dirty valve.
was adjusting the driver side camber and decide to move her out of the way of the pepper tree with leaves falling all over the place.
started her up and hear the loudest tapping noise I've heard ever from her. pop the hood put my ear down on all possible things (passenger bank valves, TB, driver side bank valves, purge valve) and yup...the noise is definitely coming from the driver side valves. giving it some gas and the noise speed up and gets less noisy and after about a min the noise completely went away. while there was the loud tapping the idle is rough and after the noise stopped the idle was better.
soooo on top of everything that are possible causes for the recent events this leads me to think maybe because the car wasn't firing properly for a while due to ignition wires dying and because the car is tuned to run slightly rich the misfire caused built up in the valves etc.
so far I've eliminated the wires, plugs, and possibly the coils (running two coil packs from the CLK to replace the one that was questionable. the CLK runs fine and the 32 still doing what it's doing).
next on the list are MAP, EGR, and dirty valve.