Technical Intermittant Throttle Loss, Low Power, Snapped Loom

[Br4vo]

Hey Guys

I have a 2007 1.4 tjet 150 67k. Ive had issue with power loss and very recently throttle cut out. I have found a snapped wire in the loom.

Will go through the issues and then the images of the snapped loom.

Ive noticed recently that my car is very sluggish in 1st and 2nd, the point at which i need to change up to keep accelarating is much much sooner its basically tap,change,tap,change to get the car moving.

Once in 3rd it feels better and i took it on the motorway over the weekend and the car still accelerated very well from 70 to 100 in 6th gear.

Yesterday i had the car repeatedly loose all throttle response at 2500 approaching 3000rpm even with the pedal all the way down, if the car was changed down or the throttle released and applied again would make the car act normally. It also did it a few times to and from work today.

I had a look in the engine bay for any loose hoses and noticed a black cylindrical sensor with 3 vacuum lines into the wastegate, intake and (i think) exhaust manifold was just flapping around the engine bay having snapped its mountings. The sensor was resting on the turbo housing. I thought the heat may have cooked the sensor or wasn't doing it any good.

Closer inspection while zip-tieing the sensor back I found the wire to this sensor was snapped and heavily oxidised on both ends. It is snapped right at the plug leaving only 10mm of wire to play with.

I cleaned the wire off with some grit paper and twist-tied the wires back together and then went for a spin.

The car feels alive again and the turbo kicks in nicely making it feel like it's back to normal but the throttle is still cutting out making it lurch forward like gearbox braking whenever the throttle is disabled as mentioned before.

So really i will need a new loom so need an idea on where to source one and i'm also concerned about the throttle still cutting out if i have fixed the boost issue. Maybe the wire is so corroded that the signal is being lost due to my bodged twist tie method? Has the car remapped itself since having to work without the input from the sensor and now needs the ecu resetting?

Car is booked into the mechanic on friday who was originally going to check for clutch slip and also the brake light sensor. I will show him the loom but willIi be able to expect him to repair it by replugging the loom or will he need to go to a wreckers?

see image for broken wire

Any ideas on where to get a new loom if it can't be replugged and how much will it cost, how much would my mechanic expect for doing the work needed?

Thanks for reading and thanks for the replies


EDIT: After Googling, i think this is the wastegate valve or such type. a N75 valve?

 

[g8rpi]

Well spotted. It is the bosst valve. Repair bepends on the mechanic. I'd expect a dedicated auto electrician to have a new connector in stock. The other option is to get a plug complete with a few inches of loom. This can then be spliced onto the existing loom. It does not have to be a boost valve plug, the connector type is common across several sensors and valves, just make sure it has the same number of contacts.

Roert G8RPI.

 

[Br4vo]

Cheers g8rpi, I didn't think to buy a new plug. Nice simple fix.

Why would I still experience throttle issues with the wire temporarily reattached? The wire tips are very oxidised and powdery mind you, perhaps a poor signal?


Thanks again

 

[Gambit1]

Hi all

I'm having a similar problem I think.
Few weeks ago my Bravo (1.9JTD MJ 07 84k) had no power whatsoever. The car worked fine for at the start of the day, but about 20mins in whenever I came to a standstill and tried to move off the car would constantly stay at low speed (like it was in 1st gear). I knew my car clutch needed replacing, so assumed it was the problem. It has all been replaced now but the problem is still there. It isn't as bad as it used to be (feels more like 2nd 3rd gear) but once I go to higher revs the power suddenly comes back.

My mechanic said he would have a look at it, he mentioned EGR valve may need cleaning or it could be a turbo issue. The car at times also does choke when moving off at low gears (its happened a few times but not always), also noticeable is when I switch the engine off (after I had power loss issues) the car judders slightly, when I have had a good run without issues the car doesnt judder at all.

Any advice and help would be appreciated, loved driving my Bravo but all these niggles are really reaching breaking point for me, please note I am awful when it comes to technical name of parts

 

[Gambit1]

Just to add, today I can hear a rattling noise in low gears (sounds like its coming from the footwell), as well as smoke coming out the exhaust every so often.

 

[markymark123]

Maybe turbo actuator sticking

 

[Gambit1]

Thanks Markymark.

I am awaiting an OBD machine, would this error show up on it?
Is it an easy fix?

I'm hoping I don't have to spend too much, already spent a fortune on a new clutch.

 

[markymark123]

I have the 1.6 multijet version which has an electronic actuator and my scanner told me it was that at fault I don't think yours is electronic so it won't tell u. What u can do is try push push up and down on the actuator rod is if it goes up and down ok

 

[Gambit1]

So armed with all this information, took it to the garages....first Diagnostic test showed up EGR Valve issue, told mechanic to test Actuator and engine manifold too.

Mechanic did all the tests, EGR valve seems fine, Turbo Actuator not sticking, the only thing he wasn't certain about was the solenoid valve, apparently I have 2 of them, 1 by the battery the other by the engine below battery.

Anyone know if this could be the problem and if its something that I can test myself?

 

[Gambit1]

Ok for some reason on start up my car is juddering quite heavily now, with lots of white smoke..... It's worse than how it was before I have it to the garage. They told me they topped up fuel while checking the car out, what chance is there that they topped up with petrol?

Really need someone to confirm white smoke, burning smell and juddering is the reason...help

 

[markymark123]

Faulty Fuel pressure regulator valve or head gasket gone maybe

 

[Gambit1]

OK everything fixed...thought I would come back and post, problems with solutions.

I did overreact with the petrol/diesel thought...may have something to do with the way the mechanic was emphasising he had topped up with diesel every so often. Anyway i'l give a low down of events from start to finish, hoping it does help someone out if they end up searching similar problems.

Bravo 07 1.9Mjet 150
Power issues
EGR Fault
Not Clutch, Turbo Actuator, Sollenoid
EGR replaced to genuine part

Car started having power issues, the car just wouldnt move in 1st gear, the clutch seemed to slip, after revving a few more seconds it would suddenly boost forward, initially it was intermittant and at times I would get caught out at the lights and stall the engine, also noticeable that the car judders when switching off engine.

Took to 1st mechanic, he said it could be a clutch problem. Suggested it could be clutch kit/flywheel etc but only way of knowing was by getting inside and it could take 9 hours to fix. Decided I would just get the clutch kit/flywheel and slave cylinder done either way as it was such a big job.

Job completed, although the drive initially felt better the power issue would still come back. At this point my engine management light (previously it hadnt been on) was on. I would also get black smoke out of the exhaust when the car was struggling. At this point I took it to a different mechanic, used his Electronic reader which was showing EGR valve leaks, he suggested EGR Valve being cleaned. Didnt cost much so told him to have a go. EGR valve cleaned, but it hadnt worked. Mechanic suggested could be sellonoid issue, but he didnt have equipment to test it. Drove home as normal.

Next morning on start up the car starting juddering violently large plumes of white smoke and an 'eggy' smell was coming out of the exhaust. Called mechanic 2 back out to fix as I was not able to get the car off the driveway, he ended up towing the car back to his garage. Went to pick it up later, he still wasnt sure what the issue was but he had blocked off the EGR valve which seems to have sorted the issue out, he had created a small hole to allow some of the fumes to get through so the engine management light wouldnt come on. To be honest the car drove well, maybe even better than it was before, but I knew it was probably going to give off dangerous fumes and may damage the turbo in the future. Thankfully when I first initially had problems I had booked it into Motor Mech (Bham) after seeing recommendations on here, only available after 3 weeks but kept the apptment.

Took car in, within a few hours it was fixed. Problem was that it was an aftermarket EGR Valve and it was faulty unfortunately some mechanic wouldnt have been able to tell it was faulty as it all looks in working order, so he slapped on a new genuine egr valve and a new gasket. They also sorted out the flashing mileage (proxy alignment or something) and my steering wheel stereo functions without me asking them at no extra cost it would seem. Car drives excellent now and hopefully wont need to spend too much in the near future on it. Also would recommend Motormech to all fiat/alfa owners, they are the only ones who seem to know where the problem is, how to fix it and all without having that 'oh man not a fiat owner again' look.

Thanks Marky for trying to point me in the right direction
Apologies for long post peeps

 

[markymark123]

Nice one, glad u got it sorted.