General 115BHP jtd engine problem /misfire

[mikelotus]

Hi there i've got a problem with my 115bhp stilo multiwagen

It has developed a problem with the engine when starting from cold it will run for approx 2 miles then it loses power dramatically and the speed drops, sometimes you can change down and it will pull through it other times it takes approx 30 secs and then comes back.
Another problem i have is that it seems to have a slight misfire / slightly hesitant on the motorway sometimes okay sometimes not.
It also puts out a cloud of diesel smoke when accelerating hard ( you can see it in the mirror when it's dark car head lights behind) but you can't see anything in daylight.
I disconnected the airflow meter drove it for 30 miles and that seemed to cure it (car wouldn't rev out properly) so bought a genuine magnetti marrelli replacement it seemed okay for 24 hours but has now started again.
If you boot it so to speak it disappears and the car accelerates no problem.
It does seem that the turbo is a little bit louder but there is no loss of power and if it was the turbo it would be smoking during the day.
It has done 130k miles anyone got any ideas ?
The next thing i can think of is the crank / speed sensor ?
I know the the EGR valve has never been cleaned if this need doing what does the moddified gasket look like and waht is the best way of cleaning it ?

Cheers

Mike
:bang:

 

[Argonought]

Sounds to me like the EGR might be sticking open.

Since EGR only operates when warm then this could be a clue :chin:

To prove it, simply block it (Search for relevant threads on how to do it)

 

[mikelotus]

Hello there thanks for the reply.

I didn't get chance to reply yesterday.

The misfire happens when hot or cold, the loss of power only occurs normally after starting from cold and within approx 4 miles of starting the car.

I ran it yesterday and it ran like a dream fantastic car, didn't used it today so don't know what it's like.

Is there a guide on cleaning the EGR valve ?

Is it an easy job ?

Cheers

Mike

 

[Argonought]

https://www.fiatforum.com/stilo/163320-egr-valve-remove-clean-modify.html

 

[mikelotus]

Re: 115BHP jtd engine problem /misfire turbo issue/ actuator

Well here is the latest update.

Took it to a local garage got them to plug the lap top into the car and no faults found or recorded in the memory. ( crypton system )
They took so live readings and air flow meter ok ( new magnetti marrelli part so it had better be) There was very little response from the map sensor so presume that it was possibly playing up.

Took the EGR valve off and cleaned it only very light powdery deposits so cleaned that out , but did find that it was sticking so freed that off and got it working oaky.

Cleaned the map sensor little bit of carbon but nothing major ( put back on the car okay ( disconnected it and the engine light came on) so reconnected it.

Left the fuel filler cap off incase a problem with that

Took off all the intercooler hoses checked them found them to be okay so put them back on again.

Moved the turbo overboost valve onto the battery tray.

Sprayed some oil onto the actuator valve.

This was Friday afternoon, parked the car up and left over night temperature was 2 degrees started the car no problem !!!! yes i've solved it i drove to Derby 33 miles no problem it was great. (05.00) ,

left it for 6 hours started it at midday drove 300yds missing and no power again :bang:

Did 80 miles with it mssing and spluttering, collected something drove it back down the motorway at 3 figures no misfire dropped to 80 spluttering again:bang:

Anyway new question, i drove the car at 40 mph in third and you can hear the turbo spinning up and then dropping down just like the missfire.
is it a problem with the overboost valve / actuator and how can i test which one it is ??.

I've sprayed oil again and will see how the car goes again tomorrow morninag at 05.00 and minus god knows what temperature.


Any help will be appreciated.

Cheers

Mike

 

[john55]

The problem is not with the overboost valve / actuator. The problem is the engine ECU opening the EGR valve at the wrong time. Block off the EGR valve and the problem will go away. Why it is not opening it correctly, I dont know but mine does the same, admitidly not as bad as yours and i have not cured it yet. I am thinking about shelling out for a new MAP sensor as it is possible this is the cause, but I havent doe it yet.

 

[Argonought]

Blocking off the EGR is easy to do and will quickly prove the case.

I'd strongly recommend you check the vacuum tubing to the VGT valve.

Vacuum supply to VGT valve should always be present.
Vacuum feed to actuator will vary dependant upon boost required.

It's difficult to check whilst driving so I'd eye-ball all the black tubing very carefully whilst bending and look for splits etc.

 

[mikelotus]

Well here is the latest in the saga, i drove it to work at 05.00 and 2.5 degrees and it didn't miss a beat !!!!!!!!

Left it parked up for 7 hours drove home and it was spluttering all the way back :bang:

Anyway didn't go out this afternoon due to the cold weather and absolutely knackered.

Will spray the oil again tomorrow onto the actuator and see what happens, will also check the vaccum pipes as suggested.

I'm on late shift tomorrow so will probably post the update on tuesday morning.

Any more suggestions will be appreciated.

Thanks

mike

 

[john55]

Don't spray oil int it. you are more likely to damage internal plastic parts with the oil rather than fix anything. The vacuum lines should be clean and dry. One thing you can do is clean the small rectangular air filter on the overboost valve.

Also block off the EGR and the problem will instantly go.

 

[mikelotus]

Hello there here is the latest update on the on going saga.

Sorry i haven't been on but wanted to see what the results were before i posted them.

Took the car out in the snow on Monday morning absolute nightmare with the surging, as so as you tried to pull away it would die and then surge with the wheels spinning really dangerous and difficult to maintain momentum.

Went out in the snow on tuesday morning and blanked off the egr valve making a gasket with an old baked been tin.

Fitted it and have been driving the car since what a difference !!!!


The car now pulls cleanly without misfiring and there is less smoke coming out of the back under hard acceleration.

It's better than when i collected the car !!.

If you are having problems then definately do this.

Finally thanks to the people who advised me what to do to correct the problem :worship:

Regards

Mike

 

[john55]

Do not leave the blanking plate in there for more than a few days. The heat / stress on it will cause the cheap metal to break free and be sucked into the engine causing damage.