C220 P1402 help

[HITECH]

Hi, thankfully this isn't my car. My m8 whoes got a c220 04 plate had his car go into limp mode intermittently and his engine light came on. So we swapped for few days so I could try get to the source. Code that came up 1st read was p1402 (EGR blah blah....). So I cleared the code and turned engine light off. Took EGR valve off and thoroughly cleaned it. Also cleaned as much of the port as I could. Put it back on and took it for a thrashing. Was good for that day. Following day it was scorching and I done bout a 20 mile drive at high speed (within speed limit of course ) then it went into limp mode. So I pulled over plugged reader into it and it was 1402 again. So I cleared it started up and it was OK. Maybe 10 minutes later after parking n switching off I get back in start it n its in limp mode again. So I drove off and while driving switched the ignition off n bumped started it again in 4. This kicked it out of limp mode and it was fine til the 20 mile journey home. Done it again. By this time engine is running warm again so its a warm engine issue I've established NOT COLD. So to rule the EGR valve out I swapped it with my own from my own car which is 100% fine. I have no problems at all with mine. His car does the same thing with my working EGR from my car in it. So swapped back over put his own back in. I've checked wiring its all fine. He hasn't had a service in just over a year now. Would an oil change make any difference since his oil defo needs changing out now. No issues with coolant or engine temps or in car heater or oil or water mixing so fine there. Any idea where I go from here.not had to investigate Dpf problems before so if I have to go down that route its new ground for me. Would really appreciate some input guys. I've searched around on here but not found any working fixes as yet. Thanx in advance.

 

[HITECH]

Anybody got any suggestions or previous experience with this error if it aint actually the EGR valve itself????

 

[Del80y]

P1402 Mercedes-Benz Exhaust Gas Recirculation Open-Loop Control OBDII Engine Light Trouble Code | Engine-Codes.com

I would suggest getting it plugged in to STAR diagnostic which is far better than a code reader you might be cheaper and faster in the long run
About 20 to 30 quid for a merc indy to do it for you .....

I bought a delphi Ds150 which is quite good for the price but I use it for a lot of vehicles

 

[HITECH]

hi cheaper and faster in the long run i doubt it very much. ive managed to save him a good few grand in repairs with a code reader and replacing anything needing replaced. I do understand the principle of the STAR system live reading but me also coming from an electronics backround i do know that majority of sensors in a mercedes kick out false positives fooling the owner into believing such n such requires replaced. Only to replace it and still have the same problem. I can gaurantee u if the car is plugged into a STAR diagnostic setup. it will come back with 1402 and they will say it requires a new EGR valve. I have already ruled the EGR valve out but fitting an identical working one into it with which the same result of fault came back. It is a hot fault. when the engine is up to temp and warm. Can stop his car turn off ignition then start it say 10 minutes later when its still warm and it will kick into limp mode with a 1402 code. No other codes present. Since its not actually the EGR valve does anybody have any suggestions at all on this. Last resort would be to plug it into a STAR. Its £38 here for that but its a complete gamble wither its going to actually come up with anything different from the 1402. I told him to keep an eye on his water and oil levels for now anyway

 

[BlackC55]

There are tests with the Star that can be done. Quite often code readers will not pick up all the codes either.

 

[HITECH]

P2A00 present after live scan

Would this error code suggest changing his o2 sensor on his CAT on bank 1 ? It would throw up a CEL light wouldnt it surely but the light does not come on. Still 1402 on standard code reader. Indy garage showed up the P2A00. What u reckon guys ???? Just to clarify the car has no running issues before or after this fault occurs. It still pulls as it should and no back firing, no black smoke, no white smoke, no whistling, no wooshing............ ??????
Im not convinced its the 02 sensor. This problem occured after he had a hose loose coolant from his radiator on a regular basis. The bottom hose right hand side beside the turbo intake one. If water had gushed out regularly over that area onto the under trays what u reckon?????

Can anybody show me where the cat sensors are, what their going to look like and easiest way to access them to change them if required?

 

[HITECH]

A little update to a stab in the dark. Diffirential pressure sensor would throw up a 1402 and a 1405 which started appearing wouldnt it? I reckon thats the wisest route to take changing a part concerning this? Especially after he had a coolant hose leak regularly. Possibly waterlogged and damaged the sensor? It ties in with the timing of the error and limp mode on his car. Coolant leaked then few weeks later the 1402 and 1405 error kicking into limp mode WITH CEL light. Anybody care to throw some input in here?

 

[MancMike]

No offense, but you'll probably get more attention to your threads if you break your posts up into paragraphs.

Everything you've posted, is massive blocks of text, which is daunting and people won't bother trying to read it all. Split up properly, and it'd be a pleasure to read as you write and punctuate well.

 

[HITECH]

paragraphed explanation

Ok fair dues.

Problem:
1402
1405
+ CEL light now
Limp Mode

Fault occured:
about 2 weeks after a coolant hose leak from bottom right radiator hose ( one beside intake hose)

Indie scan:
P2A00 ( I beleive this might be a false positive )
-----------------------------------------------------

Going by what i have red on this forum it points more to the diffirential pressure sensor.
Where abouts would this be located and is it straight forward enough to change.

No offense, but you'll probably get more attention to your threads if you break your posts up into paragraphs.

Everything you've posted, is massive blocks of text, which is daunting and people won't bother trying to read it all. Split up properly, and it'd be a pleasure to read as you write and punctuate well.

 

[Auto-mobile]

Guessing always ends up costing, you really need to get a specailist to look at it.

Regarding dpf pressure sensor it will be on the back of the airbox, nowhere near any coolant hoses, assuming the car is fitted with a dpf?

 

[HITECH]

dpf

I will go back to the drawing board for him and remove and clean out his EGR valve. Check all his intake hoses. Clean out his air filter area and check for any other visual faults.

Could his coolant leak have leaked out over the o2 sensor on the cat rendering bank 1 sensor faulty? A possibility ? I reckon there \re no coincidences with mercedes faults. One is usually linked to the other in some way or other from my own experience.

Guessing always ends up costing, you really need to get a specailist to look at it.

Regarding dpf pressure sensor it will be on the back of the airbox, nowhere near any coolant hoses, assuming the car is fitted with a dpf?

 

[HITECH]

What's the easiest method to get to and change the 02 sensors? I reckon if i change his 02 sensor and his dpf sensor job will be a good one. 1402 be gone.

 

[HITECH]

I cant find anywhere to buy a differential pressure sensor. Tried GSF and euro car parts. Where can I get one from. If I have no luck obviously I will get it from mercedes. This appears to be the culprit. 1405 more regular than 1402 with occasional CEL.

 

[HITECH]

Dead end in here for any more input. I will update again hopefully with photos and info once I get this sorted.

 

[HITECH]

Guessing always ends up costing, you really need to get a specailist to look at it.

Regarding dpf pressure sensor it will be on the back of the airbox, nowhere near any coolant hoses, assuming the car is fitted with a dpf?

Thanks for info regarding dpf sensor location. Spot on.

 

[BlackC55]

Has it been on a Star?

DPF sensor is only available from MB

 

[HITECH]

DPF sensor ordered

Its £38 for local STAR scan. But the mechanics who work in the garage who do the STAR scans are not experienced enough with mercedes cars.

More often than not the majority of mercs and bmws they scanned and replaced parts for to my knowledge still have original faults or serious faults. If they had good feedback and positive results then i wouldnt have a problem with my m8ts car going in or even puting my own car in if need be but absolutely no chance i would put use them.

I managed to get DPF sensor ordered for him. I have a suspicion its overheating and going faulty because it is a hot day warm engine fault.

A 005 153 77 28 is the part number for reference if anybody wants to know.
-------------------------------------------------------
My reasons for going for the DPF sensor replacement first is because every fault i have seen on forums about this 1402 members have spent a lot of money un-necessarily replacing EGR valves/02 sensors/MAF sensors etc etc etc and still been plaqued with the original problem limp mode problem and 1402 code.

Another sensor i had a look at was at the bottom of the intake house just under the top radiator hose. He had teh typical leak from that hose which im sure would have leaked all over this intake sensor. Is this sensor an air temp intake sensor? i will pull a pic off the net of it if anybody not sure what im taking about. Its like a mini element that is plugged into the turbo air intake hose at the bottom. I took it out , it was dry. I cleaned it anyway and checked the connector which was dry aswell.

Any more feedback would be much appreciated. Im just waiting for the DPF sensor now to fit it to his car. Thats next stage. IF FAULT STILL PRESENT THEN 02 SENSOR.

Just for your information guys, if it kicks up the 1402 error and goes into limp mode I can turn the ignition of during driving it ( still in gear as its a manual) and back on which resets it out of limp mode with the 1402 pending of course .

Has it been on a Star?

DPF sensor is only available from MB

 

[HITECH]

If I have to change his 02 sensor. Are both sensors before and after the cat the exact same sensors or different? Would make sense to change both but the code is most probably an old code which hasn't been cleared because there are no running/idling issues when its running apart from his intermittent 1402 fault which I'm waiting for dpf and iat sensor which should sort that error out.

 

[HITECH]

1402 fault sorted

The DPF sensor and IAT sensor turned up today. So I got his car and took it for a spin heat up engine get everything warm. Was doing the usual. Limp mode 1402 as soon as i started engine again after a stop. So as its been for a while now and the fault present as always.

I then cleared the code, fitted the new DPF sensor and IAT sensor with engine still warm. Now although I cleared the code, before it would instantly throw a 1402 and instant limp mode. But after fitting the new parts, started car. Job done. Fault fixed. It was a faulty DPF sensor. I replaced the IAT sensor aswell because when he had a coolant leak. It leaked all over this sensor which sits below the top radiator hose. There was no errors to indicate it was faulty but I replaced it anyway after the soaking it got.

ERROR 1402 + limp mode ( after a stop start journey n warm engine )

Replaced DPF sensor. ( which sits behind air filter box with 2 hoses stuck to it)
Replaced IAT sensor. ( which is plugged into intake pipe under radiator coolant hose)

Fault fixed!!!!
I will post hopefully 1 last post in here in a weeks time n follow up to confirm alls well but am sure it will be for him now.

The dpf sensor was a tested n working 2nd hand one which cost £15. The IAT sensor was new n cost £11. I wasn't guessing what was wrong. I was reading up every where on this specific model. After changing parts with working ones from my own car it ruled out the egr, turbo catalytic converter and a 02 sensor.
So my advice to people who want to save money is buy a basic scanner. Too many horror stories from people getting a star scan done and unfortunately given a hefty bill along with original fault still present on their car.

 

[HITECH]

question for u bud

Can u tell me if the 02 sensors before and after the cat are exactly the same. It was a question that I asked earlier in the post bud. I will be replacing my own by the end of the year as preventative measure and servicing. Have a Haynes manual in post for my car so will do them myself and a Delphi obd scanner n progger now with newest software and updates as I will be sticking with Mercedes.

Has it been on a Star?

DPF sensor is only available from MB