190E OVP Relay

[StevieJB]

Hi
Has anyone had problems with erratic engine running and replaced the OVP and cured it. The reason I ask is that the OVP relay comes up quite a few times in this forum as being the culprit, but not many people reply to say thay have solved the problem with fitting one.
My tickover when running erratic is 1100 rpm at standstill. on the move it goes up and down between 1250 and 1500 rpm surging but only when I do not touch the gas pedal.
If I sometimes stop and restart the engine it can go away, and the car runs perfect. It has been surgested that it is my OVP Relay in these forums, but because it does not do it all the time I feel as though I am throwing money at it undully. If it is the OVP for certain I have not got a problem buying a new one, it is the suck it and see I am trying to avoid.
Would the switch on the the end of the throttle cable give the same symptoms as described above if it was faulty?
Or would the Idle valve be intermitantly faulty?

 

[mercman149]

OVP problem and my car's symptoms, now fixed

I have just replaced the OVP (same as on 190) on my 230TE, but the symptoms it had were slightly different from those your 190 is displaying. The car had got gradually more and more difficult to start when cold and the ABS stopped working, causing the light on the dash to remain constantly illuminated. The only way that I could drive the car was to get it started after between 6 – 10 attempts (annoying!) and let it warm up at an idle speed about 500/600 rpm. If you tried to accelerate when the engine was still cold, the car would stall. Once warm the car idled at a normal 950 rpm and drove without a problem.
You do not say how old your car is, but what I have to do is get the mixture reset every 6-8 months because it tends to en-richen for some unknown reason as time passes.
I know the idle valve can become sticky, as my mechanic looked at the one on my car the first time I spoke to him and spayed it with a lubricant. Whether that made any difference to my problems, I don’t know, it certainly did not make them worse.
FYI - I picked up a second hand OVP from a local breaker for £15 excl VAT.

 

[television]

As the biggest problem with these relays is dry joints on the PCB, just start the car and give the relay a few hefty clouts with a large screwdriver handle,if the speed changes either resolder the thing or buy a new one. Some of these things are getting on for 20 years now, and some components do get hot, and this destroys the soldering over this period of time. None of them were very well made in the first place.

Malcolm

 

[Blobcat]

but not many people reply to say thay have solved the problem with fitting one.

That is a general forum problem not that many feedback if the advice worked for them.

 

[alanbp]

My 190 1.8 is displaying a lumpy idle, cold or warm and has on two occasions not started until the 6th or 7th attempt and even then it seems to run on 2 cylinders until it gets going. I have put in new plugs, the leads are only a 1000 miles old and fuel filter 10k miles old. Where is the OVP relay located? - I need to check this out as the idle problem started almost evernight - runs a treat at high revs and pulls like a train on the open road.

 

[television]

My 190 1.8 is displaying a lumpy idle, cold or warm and has on two occasions not started until the 6th or 7th attempt and even then it seems to run on 2 cylinders until it gets going. I have put in new plugs, the leads are only a 1000 miles old and fuel filter 10k miles old. Where is the OVP relay located? - I need to check this out as the idle problem started almost evernight - runs a treat at high revs and pulls like a train on the open road.

146 in the link

http://www.detali.ru/cat/oem_mb2.as...&L=765.902&CT=F&cat=500&SID=54&SGR=045&SGN=03

 

[alanbp]

Thanks for that - I will check it out. I had some idiot crunch my rear light lens so need to order a replacemnet from a breakers - so will try & get a OVP relay at the same time if it turns out to be suspect.

I am hoping that with it being an almost overnight sitauation that it isn't anything with the injectors!!

Thanks

Alan

 

[star]

My 190 1.8 is displaying a lumpy idle, cold or warm and has on two occasions not started until the 6th or 7th attempt and even then it seems to run on 2 cylinders until it gets going. I have put in new plugs, the leads are only a 1000 miles old and fuel filter 10k miles old. Where is the OVP relay located? - I need to check this out as the idle problem started almost evernight - runs a treat at high revs and pulls like a train on the open road.

check ur headgasket, common problem, fails on No. 4 cyl and wets the plug.

 

[alanbp]

Thanks for the advice - I had a loook under the bonnet last night for the OVP relay and couldn't find it anywhere. Behind the fuses in the fuse box was a large rectangular relay, but no others and in the separate fuse box was a single small green relay with no fuse on it.

I am slighly puzzled - does the 1.8 have an OVP relay?

On the head gasket issue - it has been replaced by the last owner about 10 k miles ago- skimmed heard & comprssion tested - the lot!! Plugs all look fine - light brown coating etc.

Can anyone advise on wether I should have the OVP ...

Thanks

Alan

 

[television]

Go to the car by the year, the electrics in the first line the at the bottom

My info shows one

http://www.detali.ru/cat/oem_mb1.asp?TP=1&F=201018&Cat=15C

 

[alanbp]

Checked out OVP last night (lurking behind the battery next to the ECU) and the fuses wereOK.

It was cold & damp last night and the tickover was dreadful - heard the distinctive tick of a HT spark and in the dark - there it was from the king lead to the clip holding it half way along & also inside the Dizzy Cap. Took this off and it was well worn with what looked like weld splatter on the contacts & the rotor plus pitting.

Orderd new from GSF and £25 for the Cap & Rotor - will try & get a king lead as well ( it didn't come iwth the HT leads set - I got from them last year)

Hopefully that will help