| Welcome to Mercedes-190.co.uk We are the Mercedes 190 owners forum, the place to be for all owners and fans of the Mercedes 190E, 190 and 190D cars. Including Cosworth (2.3 16v and 2.5 16v), EVO 1 and EVO 2 models. Modified and concourse, track cars and daily drivers, all are welcome. This free UK based forum was started back in November 2005 to serve the Mercedes 190 W201 community and now has over 9000 members from all around the world and 600,000 + posts. The members welcome you and encourage you to stay a while and have a look around. We offer you friendly chat and access to some very useful information as well as tutorials with photos and videos for many common repair and maintenance jobs. Whatever your needs there is a good chance you will be able to find what your looking for. Such as our Mercedes 190 buyers guide Sign up to gain access to all areas including for sale / classified areas and country wide meetings and events. Many forum features and sections are only available once you sign up. Join our forum at mercedes-190.co.uk! If you're already a member please log in to your account: **New members signing up** please check your junk mail for the email authorization email otherwise we cannot verify your new account. I have noticed a lot of unauthorized accounts in the system. Regards Admin |
- Pages:
- 1
- 2
| 2.6 Missfire / Hesitation / Backfire Help!; Where do I start..... | |
|---|---|
| Tweet Topic Started: Tue May 4, 2010 8:58 am (5,430 Views) | |
| NZ_190 | Tue May 4, 2010 8:58 am Post #1 |
|
Part of things
![]() ![]() ![]() ![]()
|
Ok. This has been going on long enough. I have to get to the bottom of this problem as it is really getting up my nose. Ive posted this topic before with suggestions that the DIZZY OR LEADS OR ROTOR OR OVP relay may be a fault. The dizzy / rotor and leads were all a few months old when I bought the car The OVP I took out along with the Feul Relay and gave the termanels a good clean which gave some pleasing effects but unfortunately hasnt fixed it. The engine starts within the first 1-3 turns. When cold its revs come to rest at about 800rpm. When hot its revs come to rest at about 600rpm with a little pulsing. As the engine idles it seems to run smooth then miss on a cylinder every 5-6 seconds causing the block to shake a little. When I push the pedal lightly and bring the revs up slowly all is well. But if I push the pedal moderately to hard in one go I get a instant stutter for about 3 seconds before the revs build up past 1500 rpm.....??????? I have also had the engine pop 3 times at different times over the past 2 months So far I have replaced the feul filter and started putting injector cleaner in on every fill up for the past couple weeks with no results. I have given the AFM a good clean and also the butterfly as it had an oily ring aound the edge of the flap. Thats when I noticed the pool of oil sitting in the bottom of the intake manifold.... at the lowest point just under the throttle its only a few millimetres deep but WTF is that doing there??? I also found 3 vaccum leaks 2 under the air filter and one up by the fuse box. Then tonight while testing to see if that had cured the problem. While revving the motor hard I still got the stutter and then a loud pop up through the AFM. About a month ago I made a 500km trip up the country and back the car used about a litre of oil. Where is it going?? No white or blue smoke out the back???. There is some seeping around the rocker gasket but ive read this is normal. ANy help must appreciated. Regards the confused amature 17 year old cheerz Adrian Edited by NZ_190, Tue May 4, 2010 10:57 am.
|
![]() |
|
| JFreak | Tue May 4, 2010 9:20 am Post #2 |
|
Newbie
![]() ![]() ![]()
|
Check the plugs.If they were dropped or not replaced then the gaps are probably a mile out and would cause misfire. I'd gamble on either bad gaps, or they are worn or filthy. They are only $20 form repco if you need to replace them. Don't use so much injector cleaner, you're liable to wreck something - that stuffs pretty potent! Replace the pipes or whatever it takes to fix the vacuum leaks. use some duct tape to make sure of its location before spending money on parts. As for the oil in your manifold, well I'd say that it's probably a blocked oil galley or two. Pull the PCV valve off and spray heaps of CRC into it to clean it out - it should rattle when you shake it or it's blocked up. Then run some oil detergent through the system and give it an oil and filter change. You can get oil flush at repco or gas stations. I'd recomend you do two closely spaced flush and oil/filter cahnges using half the detergent each time. Follow the directions as per a full flush on the bottle. Let us know how you get on |
![]() |
|
| NZ_190 | Tue May 4, 2010 11:02 am Post #3 |
|
Part of things
![]() ![]() ![]() ![]()
|
Cheers man many thanks. Atm it has bosch plugs in there which were in the car when I got it. I have taken them out before. Cylinders 1 2 3 and 6 were all showing the usual signs of a healthy motor but then 4 and 5 seemed prety oily and didnt have much of the usualy white deposits as the others did. So whats this mean oil is getting in there some how? There isnt any smoke coming out the back but as the car is white it does tend to get filthy pretty quick down the back after a week or so but dats prety normal isnt it?. Ive got a freind with a compression tester so ill also give that a try this weekend. Thanks very much for the advice really appreciate it. |
![]() |
|
| shrekky | Tue May 4, 2010 11:23 am Post #4 |
![]()
Troll hunter
![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
oily plugs normally indicates worn piston rings,it might not be enough that you see tell tale signs out of the back,but enough to be fouling the plugs,with a compression test,do both a dry and wet test,this will tell all .........................oil in the air filter/inlet manifold is also signs of back pressure(worn rings) or blocked engine case breather.there has been a few members on here that have had 2.6's that have had worn ring problems,site owner (merc190uk) being one of them,he had 2 2.6 engines with ring problems,so it seems quite a common problem on the 2.6's |
![]() |
|
| NZ_190 | Tue May 4, 2010 11:28 am Post #5 |
|
Part of things
![]() ![]() ![]() ![]()
|
Thanks man so sorry whats the difference between the dry and wet test? |
![]() |
|
| NZ_190 | Tue May 4, 2010 8:50 pm Post #6 |
|
Part of things
![]() ![]() ![]() ![]()
|
bump |
![]() |
|
| cosser | Tue May 4, 2010 9:12 pm Post #7 |
|
Part of things
![]() ![]() ![]() ![]()
|
Hello Mate, A wet test is when you put some oil(WD40 or 3 in 1) down onto the cylinder walls before you do the compression test. If there is a problem with the rings then the oil will temporarily seal them which should give you a higher reading than the dry test.You need to get the oil to the outer edges of the piston so that it seals the rings, so splosh a little onto the piston crown and use some compressed air to blow it out to the cylinder walls,either from a compressor or in a can which you can buy? Don't forget to unplug the lead from the ignition module on the wing (usually green to Crank position sensor) and unplug the Fuel relay so no petrol is pumped when you're spinning the engine (8 revolutions)with the throttle fully open. Do a dry test first and record the readings and then a wet test to compare. Cosser..!! Edited by cosser, Tue May 4, 2010 10:46 pm.
|
![]() |
|
| JFreak | Wed May 5, 2010 7:50 am Post #8 |
|
Newbie
![]() ![]() ![]()
|
Yeah I fully agree on the compression test. Don't put too much oil in the cylinder though or it could hydraulic itself and wreck the bearings. And like Cosser said, make sure you disable the primary ignition circuit and pull the fuse for the fuel supply BEFORE you start the test. Almost forgot - the test MUST be done on an engine at Operating Temperature. This is to ensure the end rings are fully closed so you don't get a freaky reading telling you about a crazy huge leak in the cylinders - which you don't have! lol Fouled plugs can also be caused by the air-fuel mixture running too rich or not all the fuel being burned. Check that the leads are all around the right way. And if you can isolate the miss to one or two cylinders, try swapping the plugs with healthy cylinders and see if the miss moves with them. I pull the leads one by one as the engine is running and listen for which one makes the least difference to the sound of the engine. Be careful you pull the boots and not the lead, they are expensive to replace! |
![]() |
|
| cosser | Wed May 5, 2010 10:59 am Post #9 |
|
Part of things
![]() ![]() ![]() ![]()
|
+1 |
![]() |
|
| NZ_190 | Mon May 10, 2010 7:42 am Post #10 |
|
Part of things
![]() ![]() ![]() ![]()
|
Back again, unfortunately the compression tester which I had lined up from a freind was 2 short and couldn't reach the hole and seal properly. I have played with the feul mixture screw and made the car run leaner which has helped tremendoulsy and reduced the heavy petrol smell coming out the exhaust. Idle seems better in general and on cold start the engine runs smooth. There is no hesitiation or misssfire when cold now but as soon as the engine reaches approximate running temp the hesitation and missfire is back. Not as bad as before but it is still very much there. What now??? does this narrow down the potential culprits??? Cheers |
![]() |
|
| ZAI | Mon May 10, 2010 9:02 am Post #11 |
![]()
Part of things
![]() ![]() ![]() ![]()
|
soundz like my problem too!!!when my 2.6 warms up it missfires on low revs buh i noticed couple ov days ago lead 2 was a bit loose & it had white powder in it,so i cleand it up with wd40 n then it was ok,but now its doing it again Missfire Hesitation at revs 1000 to 3500?? am guessing its a lead i hope so anyway or it might just needa service??!!! can anyone tell me if my 190e 2.6 manual 1990 has a coil pack sytem or normal??? i dont know much about the engine.....
Edited by ZAI, Mon May 10, 2010 9:03 am.
|
![]() |
|
| NZ_190 | Mon May 10, 2010 9:44 am Post #12 |
|
Part of things
![]() ![]() ![]() ![]()
|
bump for the 2 of us now haha |
![]() |
|
| ZAI | Mon May 10, 2010 10:05 am Post #13 |
![]()
Part of things
![]() ![]() ![]() ![]()
|
yep guess so....buh av notice a box near front ov engne wer the leads go... is it a coilpack??? if so thats the problem!!!! i had few golf vr6 wiv coilpack nacking up!!!!n they do the same juder misfire ect ect i mite need a new coilpack..............but am still not sure if its a coilpack or a standard diz cap system on my 190e 2.6???........ |
![]() |
|
| ZAI | Mon May 10, 2010 10:07 am Post #14 |
![]()
Part of things
![]() ![]() ![]() ![]()
|
plus its raining so no chance ov doing the engine today!!! al crack on wiv the stork today |
![]() |
|
| NZ_190 | Mon May 10, 2010 10:11 am Post #15 |
|
Part of things
![]() ![]() ![]() ![]()
|
That black cover on the front of the motor where all the leads go is the distributer but if you look of the right hand side there should be a single cable coming out which if you follow along leads to the coil. Is this what you mean??? Sorry gettin bit of track any more suggestions on my motor anyone lol??? |
![]() |
|
| ZAI | Mon May 10, 2010 12:35 pm Post #16 |
![]()
Part of things
![]() ![]() ![]() ![]()
|
i dunt know its my first 190e............wot av i got myself into!!!.....well if that coil lead is anything to do wiv the distributer then it myt be the problem with yours!!?..........if not nz190... take it to the garage....thats what i intend to do when av fixd mine up.
Edited by ZAI, Mon May 10, 2010 3:10 pm.
|
![]() |
|
| NZ_190 | Mon May 10, 2010 9:10 pm Post #17 |
|
Part of things
![]() ![]() ![]() ![]()
|
bump |
![]() |
|
| NZ_190 | Mon May 10, 2010 9:11 pm Post #18 |
|
Part of things
![]() ![]() ![]() ![]()
|
Back again, unfortunately the compression tester which I had lined up from a freind was 2 short and couldn't reach the hole and seal properly. I have played with the feul mixture screw and made the car run leaner which has helped tremendoulsy and reduced the heavy petrol smell coming out the exhaust. Idle seems better in general and on cold start the engine runs smooth. There is no hesitiation or misssfire when cold now but as soon as the engine reaches approximate running temp the hesitation and missfire is back. Not as bad as before but it is still very much there. What now??? does this narrow down the potential culprits??? Cheers |
![]() |
|
| ZAI | Fri May 14, 2010 8:11 am Post #19 |
![]()
Part of things
![]() ![]() ![]() ![]()
|
i was just reading on electrical issue n sum guy was ona about OVP relay???? he had to rev it past 4 rev,s so his car was running ok,......it might be the OVP relay on your car??..........av found my problm it was a dodgy lead.........i hope this helps |
![]() |
|
| NZ_190 | Mon May 17, 2010 11:13 am Post #20 |
|
Part of things
![]() ![]() ![]() ![]()
|
Thanks man but I dont think so I have taken it out and had a good look and it seems fine fuse is good too. I have the dreaded feeling my problems are much more mechanical. The car is using oil. Mayby about 1 litre per 600-700 km... Some times when I first start the car i get a bit of white smoke or residue in the exhaust pipe which does clear after 5-10 mins. I have never had to top up the water so I cant see the headgasket being the problem. Is it possible that if not the piston rings the vavle stem seals have failed??? I had my brother rev the car up while standing behind recently and have notice that small spits of oil are coming out the exhaust... I have also been having a further fiddle with the vaccum lines. I notice that around the idle control unit it looks as if the pipes have been removed before sometime in the past as there is sealent around the join. I have continued to look for more leaks in the vacum system i noticed 2 of the lines are conected sum where under the amf unit and its impossible to see or even acess where the lines are going. How are these connected because I have a feeling they are perrised as I must have moved them slightly which has now made the problem worse as the car now starts fine but then as the revs come down agen the engine starts pulsing madly from about 500 to 900 rpm. When I move into reverse or driv the engine almost stalls and turning the wheel at the same time puts too much load on the motor causing it to stop. Cheers for all th advice already anything else will be much appreciated |
![]() |
|
| NZ_190 | Mon May 17, 2010 9:29 pm Post #21 |
|
Part of things
![]() ![]() ![]() ![]()
|
bump |
![]() |
|
| Mohammad | Mon May 17, 2010 11:49 pm Post #22 |
|
weneakhborz
![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
to reply on your first post,about the miss Fire and hesitation my father's w124 with m103 3.0 is doing that for over three years now. we have done every thing,one thing left there is to change the whole intake side. reading some where on the Internet,i've read about this guy with a mercedes V8 who had the same Problem.he said he knew how to fix it.let me see where was that post.. while i search for it... we asked for the Price of the part that guy changed..it was a bit costly.so my dad kept it,as he doesn't notice the missfire when he Drives. i can't find the topic..it was on MBworld.org IIRC. any way.i don't know what is the name of the part he changed... it is the Black round thing "and i found that some times it is naked copper'.under the throttle Body i think it is the return fuel pump???? i don't know |
![]() |
|
| Mohammad | Tue May 18, 2010 12:24 am Post #23 |
|
weneakhborz
![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
wait wait.. now iam remembering things.he changed the Fuel pressure regulator "1" and this Black round thing i don't know what is it called."2" ![]() |
![]() |
|
| NZ_190 | Tue May 18, 2010 12:44 pm Post #24 |
|
Part of things
![]() ![]() ![]() ![]()
|
MANY MANY THANKS
|
![]() |
|
| Mohammad | Tue May 18, 2010 3:55 pm Post #25 |
|
weneakhborz
![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
i hope it does help. |
![]() |
|
| NZ_190 | Thu May 20, 2010 10:55 am Post #26 |
|
Part of things
![]() ![]() ![]() ![]()
|
Today I went to our local mechanic. He is a friendly german guy who knows these carz backwards and forwards. I mentional all of the above in this post to him and he also took the car for a drive. He reckoned that the surging idle is a isolated problem to the miss and backfire problem and could be the part that weneakborz is talking about. As I also told him bout the unusally high oil consuption he then proceeded to look at what was coming out the back while revving up the engine. There was almost no visible fumes at all and not even slightly blue. He said that it may well worn valve stem sleals causing the leak. And regarding the oil siting in the bottom of the intake manifold he said that was due to the breather pipe and has just built up over the years. Bearing in mind that this was a totally free of charge breif inspection I was very happy. He said that for a valve stem or 4 to be replaced could cost in the vacinity of 200-500 NZD which is pretty good buy what I have read on the forum for other engine related repairs. That would equate to about 80-200 pounds roughly. So I am probably going to get the car booked in for next week. Just thought I'd throw it up on here and see what you guys thought of his analysis. IS IT COMMON FOR VALVE STEM SEALS TO GO ON THESE M103 ENGINES????? CAR HAS 210 000km on the clock CHEERS ADRIAN Edited by NZ_190, Thu May 20, 2010 12:25 pm.
|
![]() |
|
| Mohammad | Thu May 20, 2010 12:12 pm Post #27 |
|
weneakhborz
![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
please report to us what happens with the missfire thing, |
![]() |
|
| bolide | Thu May 20, 2010 5:46 pm Post #28 |
|
Bolide
![]() ![]() ![]() ![]()
|
Yes Nick Froome |
![]() |
|
| NZ_190 | Wed Jun 16, 2010 9:06 am Post #29 |
|
Part of things
![]() ![]() ![]() ![]()
|
Long time since, but I am back with news. I brought the car in last week on the wednesday. It is now one week later exactly. The stem seals have now been changed whcih was a suprisingly easy job (i watchd :P) so the oil usage will now be back to normal hopefullly. He is no adressing the hesitation missfire which is proving very difficult as many other people on the forum no im guessing. 2 days before bringing it in I took the Idle Air Control Vavle out and gave that a good clean along with this I also purchased so hose clamps and made sure the seal on the valve to the pipes was tight as it had looked like someone was in there before and traces of a poorly done sealant job was still there. Engine hesititation missfire Under intial inspection he recconed it was an ignition missfire as it was missing on all cyclinders under abrupt acceleration and then backfireing up through the afm. He has put new plugs in which has helped the rough idle problem tremendously so this must have been due to the servirely fouled and over rich running state it was in before i took it in. He has also tried a replacement cap and rotor with no luck. He said the leads look good too. This only leaves the feul distributer. He told me tonight that he was going to source one at his other work shop and try get it installed tomorrow morning. Fingers crossed this cures the problem =) Other wise from what i have been reading on the forum it cud be the: -ovp -feul realy -coil -ingnition module Anything esle? that any of you guys have had cause a problem like this? Regards Adrian **** AND OF COARSE THE FEUL PRESSURE REGULATOR ILL MENTION THAT TO HIM TOMORROW**** Edited by NZ_190, Wed Jun 16, 2010 9:08 am.
|
![]() |
|
| NZ_190 | Wed Jun 16, 2010 11:02 am Post #30 |
|
Part of things
![]() ![]() ![]() ![]()
|
bump |
![]() |
|
| NZ_190 | Wed Jun 16, 2010 12:21 pm Post #31 |
|
Part of things
![]() ![]() ![]() ![]()
|
bump |
![]() |
|
| arkudos | Wed Jun 16, 2010 12:45 pm Post #32 |
|
Still a Noob
![]() ![]() ![]() ![]()
|
Don't know if this helps... but mine stuttered when cold, took it to a specialist, he also said I might need a fuel distributor, but decided to do some tests OVP all the other minor which resulted in my computer (brain fart whatever it's called)) wasn't getting 12 volts... fixed the problem. |
![]() |
|
| NZ_190 | Thu Jun 17, 2010 9:26 pm Post #33 |
|
Part of things
![]() ![]() ![]() ![]()
|
Thanks mate could you please explain that I having trouble understanding Thanks for the help
|
![]() |
|
| NZ_190 | Tue Jun 22, 2010 7:01 am Post #34 |
|
Part of things
![]() ![]() ![]() ![]()
|
Picked up the car tonight with a replacement feul distributer. The mech had the car running up for a while and did some tests before I arrived so he reckoned it was all good now, He sed take it for a cuple days and let me know how it goes. From the first turn of the key I could already tell something had been dirastically improved, the car fired and came down to a nice steady idle which it never did when warm. The initial drive was awesome the throttle responce seemed miles better the power band came on allot eriler and best of all no hestiation even on full throttle. I took the car home the longest way possible and just as i was turning into my street. it chugged across the road ....... what the bloody hell!!!. The problem is now only occuring when I jab the throttle down quickly to half way or so and otherwise its perfect. Any ideas.. |
![]() |
|
| NZ_190 | Tue Jun 22, 2010 7:10 am Post #35 |
|
Part of things
![]() ![]() ![]() ![]()
|
bump |
![]() |
|
| arkudos | Tue Jun 22, 2010 7:29 am Post #36 |
|
Still a Noob
![]() ![]() ![]() ![]()
|
Sorry mate for before... are your electricals all in order, MY "ECU" non cat was not getting 12 volts, so it wasn't passing (full 12 volts) it to the fuel distributor so my was only mechanical injection! That's what I meant previously. |
![]() |
|
| NZ_190 | Tue Jun 22, 2010 11:42 am Post #37 |
|
Part of things
![]() ![]() ![]() ![]()
|
Ohh kk in fact my mech gave me a spare feul distributer ecu control thingy, lol not sure of it proper name the bit that is screwed to the side of the distributer which is connected to the ecu. He told me to try swap them over and see if that makes a difference. So ill try that when I get a spare moment. Cheers mate ill check all the wiring to, I was planning to take out the relays and stuff any way and give them a good clean too. On a nother note my tacho is bloody bouncy. whats causing thisis this a bad sender or someting of the sensor on the alternator or where ever the reading is coming from? |
![]() |
|
| sportline_stu | Tue Jun 22, 2010 12:37 pm Post #38 |
![]()
More than part of things
![]() ![]() ![]() ![]() ![]()
|
Mine need doing on my 2.6. The car runs fine, but takes a bit of effort to start if left overnight due to the oil dropping down and needing to be burned off. I also need to top up the oil fairly often, but the car has no running or idle issues. Stu |
![]() |
|
| Mohammad | Tue Jun 22, 2010 1:13 pm Post #39 |
|
weneakhborz
![]() ![]() ![]() ![]() ![]() ![]() ![]()
|
i would say check the Fuel Pump and then check for Electrical failures |
![]() |
|
| NZ_190 | Sun Jun 27, 2010 7:52 am Post #40 |
|
Part of things
![]() ![]() ![]() ![]()
|
Thanks mate the mech recons the feul pump is alg hes going to try some other bits this coming wee. Is there anyone else that has encountered a similar prick of a problem. Any ideas on the tacho problem and where / how to fix it? |
![]() |
|
| 1 user reading this topic (1 Guest and 0 Anonymous) | |
| Go to Next Page | |
| « Previous Topic · Engine · Next Topic » |
- Pages:
- 1
- 2







![]](http://z2.ifrm.com/static/1/pip_r.png)




.........................oil in the air filter/inlet manifold is also signs of back pressure(worn rings) or blocked engine case breather.

Thanks for the help


3:15 PM Jul 11