2001y 210 e320 4-Matic Wagon. P0300/1/2/3.

[dkveuro]

Have posted again here in 'Tech Help' as 'Techs Only' gets very little traffic....hope I have not stepped on anyones toes.

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From 'TECH ONLY' Post.:

2001 210 e320 4matic Wagon. P0300/1/2/3.
Hi folks...

I have closed my shop as of January after an life altering illness. I'm recovering, but have little strength or stamina and am subject to some information delete !

Not looking for sympathy...this is just an FYI to get you up to speed.....but I do need some input. I have a 20 plus year customer who has been 'everywhere' to try to get this 215,000 mile beast to perform because she knew I had closed the shop..but in desperation has turned to me.

I scanned it and found 24 codes.... ranging from MAF to KAT performance and about everything in between. The right KAT had been replaced in 2008 for similar problems by Mercedes. This assembly consists of the down pipe ( bolted to the manifold.) with two O2 bungs, B1 and B1 B2 and two catalytic housing all in one pipe.

The left side is OE factory original 2000yr. Scanning B1 and B2 O2's shows good wave form and B1B2 hovers around 500mV with a slight ranging and flat lines when cylinders 1/2/3 miss fire.

I am getting constant 1/2/3... P0300 P0301 P0302 P0303 as soon as the engine is rev'd or hold rpm at 3500 rpm. Up to this miss-fire point, O2 all performing correctly . Switch ign' off/on and all firing again on reset.

New are the following.
MAF.
Bank 1, 3 Coils.
All spark plug wires...12 of 'em.
Spark Plugs.

Found Bank2 ( 4/5/6 cylinders.) second cat' broken up and plugging the entry to the muffler. Removed all and dropped B2 exhaust pipe pipe and check for obstruction. Found primary cat' okay and is performing okay as far as B2 O2 reading concerned.

Now please remember... 1, 2 and 3 are miss-firing, but broken cat' was 4, 5 and 6 cylinder side.
The secondary cat's are not 'monitored'.

Road test reveals miss-fire will only happen on WOT over 3000rpm or 3/4 throttle at 4100 to 4500rpm in any gear......CHECK ENGINE lamp will flash.

Before I do anything else...does anyone know what I am missing here? Doctor told me I wouldn't know what I had forgotten and am wondering if this is happening to me now.

BTW...I swapped the coils from bank to bank with no change. When the codes are cleared, car accelerates like it should until WOT or 4000 plus rpm triggers miss.

Thank you for your time. I no longer am member of iATN, so not able to post there now.

regards

[dkveuro]

UPDATE:
Have performed a cylinder balance test and it showed each cylinder dropping out the same. Warm Engine Balance test screen shows #2 cylinder occasionally having a .03 reading....although it is mostly all cylinders 0.

Am about to run a load test and watch the injectors for running lean by watching B1 and B2 b1 oxygen sensors on a dual graphing screen..


regards


.

[97 SL320]

P0300 is random missfire, I take this to be random over many cylinders. It looks like that 1,2,3 miss fire often enough to trigger a single cyl missfire code.

What direction does the fuel rail input run? If 4,5,6 get fuel first, 1,2,3 could run lean and missfire. What is the fuel pressure under load? Any recent work on this car? What if the fuel cross over rail is crimped between between the left and right.

Also, is there a dual intake manifold system on this car? Perhaps there is some sort of interaction there.

I know on a 97 C280 M104 SFI ME2.0 ( ME 2.1 ? ) , dropping a cylinder for 15 sec or so will shut the injector of that cyl down until the key is cycled again.

[dkveuro]

Thank your for your reply.

I have now completed the following tests and swaps:

Fuel Pressure Idle: 55psi. Drops 10 psi or so under WOT and steady 53psi to 55psi cruising at 70mph. (Pressure gauge taped to windshield.)

Full load test up to 4600 rpm on the road and no miss and full power..
Full Load test over 4600 rpm...heavy drop in power and flashing Check lamp.

Check for which cylinders drop out on scanner: Always P0300, P0302, P0303 P0301. This is the order in which the scanner lists the fault codes. Tried this 3 times and always same result. .

Run road test over 4600rpm to provoke miss-fire and when checked at the coils.....always cylinders #1 and #3 coil packs have been cut off by ECU. #2 is still firing when checked by pulling coil loom connector off and not cut by ECU although the code set includes P0302..

Swapped coil from #4 to #1 cylinder and this brand new coil is now found to be cut off by the ECU on return from road test....so still common to this #1 cylinder although original old coil works fine in #4 position. I never get 4, 5 or 6 cylinders dropping out.

I'm beginning to suspect high speed injector problem on maybe all injectors,(?) although the slump in power as miss-fire is detected is drastic. ...takes another 10 seconds of WOT to climb to 5300 rpm after miss-fire detected....during which time no change in fuel pressure.

I have watched the O2 on both banks under all sorts of driving conditions and they are reporting no lean condition. So, I have no 'Rich Stop Reached' codes or condition which lean injectors would trigger.

When ECU shuts off #1 and #3 on road test, the O2 nearly flat lines and will range maybe 250mV to 400mV while the Bank 2 is normal....and back at the shop, #1 and #3 are dead.

Don't see fuel pressure as a problem, although I am suspecting injector/s. power up to 4600 rpm is great and all scanner tests get a pass.


regards

dk



.

[97 SL320]

Originally Posted by dkveuro

Fuel Pressure Idle: 55psi. Drops 10 psi or so under WOT and steady 53psi to 55psi cruising at 70mph. (Pressure gauge taped to windshield.)

Is this fuel pressure regulator referenced to manifold vacuum? If so, pressure should rise the higher the load / lower vacuum.

Originally Posted by dkveuro

Run road test over 4600rpm to provoke miss-fire and when checked at the coils.....always cylinders #1 and #3 coil packs have been cut off by ECU. #2 is still firing when checked by pulling coil loom connector off and not cut by ECU although the code set includes P0302..

The ECU isn't going to cut out spark, it will shut off an injector to prevent raw fuel from overheating the cat.

Originally Posted by dkveuro

I have watched the O2 on both banks under all sorts of driving conditions and they are reporting no lean condition. So, I have no 'Rich Stop Reached' codes or condition which lean injectors would trigger.

The short and long term fuel trims likely won't react fast enough from the time the ECU sees a missfire and when it shuts off the offending cylinder.

Originally Posted by dkveuro

When ECU shuts off #1 and #3 on road test, the O2 nearly flat lines and will range maybe 250mV to 400mV while the Bank 2 is normal....and back at the shop, #1 and #3 are dead.

Yes, since 1 and 3 are pumping air, O2 voltage will drop.

Originally Posted by dkveuro

Don't see fuel pressure as a problem, although I am suspecting injector/s. power up to 4600 rpm is great and all scanner tests get a pass.

regards

dk.

[dkveuro]

The fuel pressure drops about 8 psi when suddenly opening the throttle. It then climbs back to 55 psi under part throttle and remains at approx' 55 psi on road test.

I did not check the vacuum change to pressure you would normally expect as there is no hesitation . I will do that tomorrow.

I am sending all the injectors for sonic cleaning and checking to eliminate them as a contributing problem.

regards

dk

[dkveuro]

Fixed ! Runs well.

I swapped injectors, coils...nothing. Swapped back to old MAF....much worse. New MAF back in...ran Adaptions . 5500rpm gear shifts as smooth as you like. Tach's out to red line (In low gear, you understand.) No codes after 20 miles road test, city and rural.

So...I'm thinking this Adaptions after using the old MAF took, whereas, maybe the first adaption after new MAF origonally installed, didn't ? Wadda ya know ?

So this is down to Alain V on the Tech's Only forum. I must say, the first Adaptions allowed the engine to run okay'ish but how would adaptions not take ?

Thank you all for your suggestions. Car back with owner this afternoon. Why does Mercerdes want $600.00 plus for the MAF anyway ? VW was selling MAF's for $60.00 a little while ago. Admitted they are not whittled out of a peice of tree, but still !


regards

dk


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