Technical Fiat Stilo 1.9jtd 115bhp, stuttering and hesitating intermittently

[suitw2000]

Hi, Im new to the Stilo and have a 2003 1.9jtd 115bhp Estate, 110,000 miles with full service history and one owner before me from new. I have just bought the car a few days ago and it drives with no warning lights, it has the preheat message and is going in for new glow plugs at a Fiat specialist next week, had a look, a mare of a job, no thanks! I thought, i am a competent basic DIY mechanic.
I have an issue when driving the car, it is intermittently stuttering, hesitating, instant drop in power that is for 2 seconds and then disappears. I took the EGR off yesterday and cleaned it. The centre solenoid spindle was free and I put it all back on. The car has no nasty smoke and runs at normal temperature and accelerates normally. I am running through some Redex diesel cleaner at the moment as a precaution as the car is new to me and seems to have done short runs prior to me buying it.
Today I changed the oil and air filter, the maf sensor was oily and i cleaned it with electrical contact cleaner, all the pipes near the maf and airbox were covered in old oil so I cleaned them all with brake cleaner, I syringed out the trap below the airbox and cleaned the breather from the centre of the rocker cover to the pipe near the maf. It worried me a bit all that oil in this area.
The main issue is the stuttering, can I sound you all out as to what is causing this?? faulty EGR? Boost control valve? Turbo seals?? - No dodgy smoke though. Blocked breathers, fuel filter - recently replaced 3000 miles ago. Stuck injector or clogged injector??? or is it linked to the failed glowplugs at the moment. I am at a loss as to what may be causing this, love the car, drives lovely but just the stuttering and hesistation now and then. seems to be getting more frequent though. Any help appreciated.

 

[Yorkshire007]

I would check the earth's, and then the condition of the battery. The cold weather doesn't help. I have swapped out the glow plugs and the preheater too. I did get the local garage to sort it out for me.

 

[Ralf S.]

You have an intake leak which may or may not be part of the problem.

The oily pipes down by the airbox suggest one of the various clips is loose, or the soft rubber 90-degree pipe at the top of the metal pipe might be split. That oil is coming out from somewhere. While you're down there, make sure the blue pipe to the electro-boost valve is not split and still on the valve. Also check that the rubber pipe you can see from the n/s/f wheel arch is not worn through on the wheel-arch liner.

If your MAF is oily (by the airbox) then that suggests that at some point there was too much oil in the sump. I only ever fill mine up to 80% and it's not too bad between services (cleaning out pools of oil). Before then, someone had overfilled it and the oil was *everywhere*.. proper puddles of it in the airbox, in the trap and in the inlet manifold.

If yours suffered the same problem then check the MAP sensor on the back of the inlet manifold. It looks like an open "L" shaped piece of plastic aboot 6cm long.. but it's plugged into the back of the manifold. If you have your own personal oil well in there, the MAP sensor could be full of oil and giving a duff reading to the ECU. A new one is better than a clean-out but they're quite dear, so clean yours out first and see if it improves things, even if not completely, before spending any money.

I'd also check the Coors can on the bulkhead, aka the fuel filter. They're supposed to be changed every service but I ran mine for 48,000 miles since I was waiting for a "Water in fuel" message that never arrived. You could have a clogged/watery fuel filter.

Glow plugs are like very fragile spark plugs. If you have a 10mm glowplug socket (1/4 " drive so you can feel how much force you're using) then they'll come out fairly simply.. if they're not stiff in there. The proper socket has a joint in it, to allow it to bend in the right places.. otherwise it's like removing a spark plug.

Give the beast some Cataclean every so often.. it'll help keep the injectors clean. The issue *could* be an injectore but if it is, you should be able to find an error code in the ECU, if your specialists can have a read while it's in there. Later you should invest in the Fiat Multi0scan software and a reader... they come in handy for all sorts of issues.


Ralf S.

 

[suitw2000]

thank you both, unfortunately the morning after servicing the car it was a no start and i replaced the crank sensor, glow plug control module and cleaned out the MAP sensor, unfortunately it still would not start. Had it recovered to the Fiat specialist today and he rang me to say there were 6 stored codes in the ECU, including the timing being out of synch with the revs --- ? cam position sensor maybe??? or timing belt one tooth out, was changed 2 years ago. I will update once I have more updates, get the feeling it is not going to be an easy fix. thanks all for your suggestions so far appreciate your help.

 

[suitw2000]

Finally got to the bottom of this one, it was the cam sensor, this has been replaced, new cambelt kit, new glowplugs and boom it fired right up, the garage, a Fiat specialist deserves a mention, Nick Harper in Norwich, He is brilliant, reasonably pried and very knowledgeable, he knows Fiat and Alfa Romeo inside out. Just the MOT to get through now, New Pirelli winter tyres to fit and a new exhaust. Fiat Fun ontinues, thanks to all that responded, this forum is really helpful.

 

[Ralf S.]

Good job!

The thing I've found with Stilo is that small issues can cause quite bizarre symptoms, out of proportion to the original problem. You can get all sorts of strange symptoms and it turns out that a bolt on the rear number plate is loose, or something like that.

On the other hand... my high beam wasn't working and I thought that would be a bulb or simple circuit issue, whereas it turned out to be a problem in the Body Contol Module box under the fuse box. Joy!


Ralf S.