Technical urgent help!!! power loss in HGT
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Technical urgent help!!! power loss in HGT
you dont need to reset the ecu after fitting a new MAF. i reset it every time i touch anything because i'm a good boy and i always disconnect the battery before starting work. i
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Hi Siniper,
I have exactly the same problem on my 155 HGT. I have tried everything you have tried:
Fuel pressure - 3.5-4bar (holds pressure after engine is switched of as well)
Compression Over 200 psi per cylinder
MAF changed for genuine Bosch part (twice!)
Fiat Examiner shows no fault code
Timing checked - ok
Lambda sensor output checked
Back pressure test carried out
Air fillter replaced
New spark plugs
Still really lacking in power, all garages I have taken it to have said it is the flattest 5 cylinder car they have driven.
If you do find out what is wrong, let me know as I can't think what to try next!
I have exactly the same problem on my 155 HGT. I have tried everything you have tried:
Fuel pressure - 3.5-4bar (holds pressure after engine is switched of as well)
Compression Over 200 psi per cylinder
MAF changed for genuine Bosch part (twice!)
Fiat Examiner shows no fault code
Timing checked - ok
Lambda sensor output checked
Back pressure test carried out
Air fillter replaced
New spark plugs
Still really lacking in power, all garages I have taken it to have said it is the flattest 5 cylinder car they have driven.
If you do find out what is wrong, let me know as I can't think what to try next!
is the variator working? that would affect cam timing causing a power loss above 3500rpm
hi jug,
thanks for replies and I have some more questions for you.Timing sensor (cam sensor), crankshaft position sensor (rpm/tdc sensor) and knock sensor could be the problem? Can you tell me what the abbreviations IACV and ISCV stand for?
I heard from someone in here in Ankara that 97 and 98 hgts suffered from variator.In order to prevent these mistakes authorised dealers called the owners and changed the engines.But in that time I got no calls from the factory and the dealer.Did you hear something like this?
How can I check the variator? Can I do that by myself or a authorised dealer is needed?
Again thank you very much for your replies.
see you
thanks for replies and I have some more questions for you.Timing sensor (cam sensor), crankshaft position sensor (rpm/tdc sensor) and knock sensor could be the problem? Can you tell me what the abbreviations IACV and ISCV stand for?
I heard from someone in here in Ankara that 97 and 98 hgts suffered from variator.In order to prevent these mistakes authorised dealers called the owners and changed the engines.But in that time I got no calls from the factory and the dealer.Did you hear something like this?
How can I check the variator? Can I do that by myself or a authorised dealer is needed?
Again thank you very much for your replies.
see you
hi cornholio,
I have been working on this issue for about 2 months. As I mentioned before we checked the major causes and still working on it. If we find something I will tell you. If you find we are waiting for your call.
keep in contact
I have been working on this issue for about 2 months. As I mentioned before we checked the major causes and still working on it. If we find something I will tell you. If you find we are waiting for your call.
keep in contact
crankshaft position sensor would cause more serious problems like cutting out and a very erratic idle. this fault does not always show up on a diagnostic, but the symptoms are so noticable that you couldnt miss it.
a faulty knock sensor would cause ignition timing to be retarded (by approx 5degrees) so you would get a loss of performance. this could be your problem, however a fault that results in retarded ignition must also result in an error code been stored in the ecu. if you dont have a code (such as P1225) then your ignition is not retarded so you can rule this out.
a faulty cam sensor can cause a variety of fueling and ignition problems, and like the crank sensor it doesnt always trigger a fault code. my gut instinct tells me your problem is not the cam sensor, but in your situation i would replace it just to be sure.
idle air control valve and idle speed control valve, both mean the same thing. basically there is an actuator that moves to alter the amount of air that passes through the throttle body, this alters the idle rpm. if your car has an idle rpm that does not adjust to maintain the 850rpm when warm, and does not increase to a higher rpm on a cod start, then your iscv could be faulty, well the actuator is the part that will be faulty. your problem doesnt mention an idle issue so this cant be your fault.
i have never heard about a recall, but the variator is a common fault on almost every fiat group engine that uses one so it would be wise to change it at the same time as the second timing belt change (approx 70k).
you can tell if the variator is faulty, when you start the engine it will sound a bit like a diesel. you can also reomve the timing belt cover and watch it to see if it moves when you rev the car, it should move the pulley at higher rpm.
Siniper,
Fixed my Bravo today and it is running really well :slayer:. This is the repsonse I posted in my 'HGT Lacking Power' thread on this forum:
IT'S FIXED!
Yesterday the exhaust broke where the manifold bracket attaches to the downpipe (near the Lambda sensor). The bracket that is welded onto the manifold sheared off. Think it was something to do with hitting a massive pothole at the weekend. Anyway, took the car to a local garage who welded the bracket back onto the end of the manifold. £30 later the car is running like a dream and pulls really well now.
I think there must have been a fault all the time with the manifold meaning that air was leaking into the exhaust just in front of the Lambda sensor, making the lambda sensor send the wrong signal to the ECU.
So £500 and many hours of scratching my head later the car is sorted following a £30 weld!
Might be worth checking the same part of the manifold on yours. It is strange as the exhaust was not noisy or blowing until it completely separated from the manifold yeaterday.
My car has never run this well from the day I bought it (July 2006!!).
Fixed my Bravo today and it is running really well :slayer:. This is the repsonse I posted in my 'HGT Lacking Power' thread on this forum:
IT'S FIXED!
Yesterday the exhaust broke where the manifold bracket attaches to the downpipe (near the Lambda sensor). The bracket that is welded onto the manifold sheared off. Think it was something to do with hitting a massive pothole at the weekend. Anyway, took the car to a local garage who welded the bracket back onto the end of the manifold. £30 later the car is running like a dream and pulls really well now.
I think there must have been a fault all the time with the manifold meaning that air was leaking into the exhaust just in front of the Lambda sensor, making the lambda sensor send the wrong signal to the ECU.
So £500 and many hours of scratching my head later the car is sorted following a £30 weld!
Might be worth checking the same part of the manifold on yours. It is strange as the exhaust was not noisy or blowing until it completely separated from the manifold yeaterday.
My car has never run this well from the day I bought it (July 2006!!).
hi cornholio,
today we checked the manifold bracket that you mentioned yesterday.no problem.also we took down the catalytic converter and fixed an exhaust silencer instead but the result is same laking of powerrrrr(
I am thinking of changing the lambda sensor.However there is no fault code on examiner about the lambda.
what do you suggest?
today we checked the manifold bracket that you mentioned yesterday.no problem.also we took down the catalytic converter and fixed an exhaust silencer instead but the result is same laking of powerrrrr
(I am thinking of changing the lambda sensor.However there is no fault code on examiner about the lambda.
what do you suggest?
Attached is am image of the weld to check. It may not be obvious if there is a problem with the weld so may be worth smearing some exhaust sealant around the joint as a quick check.
You can check the output of the Lambda sensor using a multimeter on the output wire and checking the output signal voltage and rate of change whilst driving. I will let you know the voltages and which wire to attach the multimeter to later when I check my e-mails.
Good luck.
You can check the output of the Lambda sensor using a multimeter on the output wire and checking the output signal voltage and rate of change whilst driving. I will let you know the voltages and which wire to attach the multimeter to later when I check my e-mails.
Good luck.
imo it cant be the fusebox. i'm not sure what you mean by electrical system, the whole car is an electrical system
i cant think how an electrical short or bad conneciton could cause powerloss without causing other obvious electrical problems that you would notice, so imo it that cant be your problem.
where is the exact location of knock sensor in hgt? there is a button under the driver's seat I think this is the part of it but I want to know where is the other part which is located under the hood.
and also the location of cam sensor? how can I reach that sensor? is it hard to reach?
again thanks a lot
and also the location of cam sensor? how can I reach that sensor? is it hard to reach?
again thanks a lot
