Problem with my car - Hesitating
#1
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I ran my car at Elvington earlier on this year, and the moment the car hit 3-4k it hesitated and started jerking violently. The car was fine on the back roads on the way there however, so there were no signs of any problem. Once passed 6k this problem dissapeared.
I initially put the problem down to the spark plugs causing a misfire, as thats the sensation that was happening.
I have this morning changed my spark plugs (They were long over due and havnt been changed in about a year) The car had NGK6's and after taking them out it was obvious they were no good anymore. I have replaced them with NGK7's and when started up the car did actually sound as though it was starting better.
I then took the car onto the bypass to see if this had cured it. I accellerated slowly and once again at 3-4k it started hesitating. So although i have done some good by replacing the old plugs they werent a cause of the problem, or the main cause anyway.
I have gone all around the engine bay checking all cables wires, hoses etc to ensure they are all connected properly and they all seem fine. The air filter was also cleaned whilst the plugs were changed.
The only things i can think of now are possibly the coil pack and or ignition leads need changing. Ultimatly the ECU may even be at fault but im thinking its one of the former.
Obviously the car isnt any fun to drive at the moment and i would apprieciate any help and advice on the matter. I have been to Subaru and they fobbed me off by saying unless the engine management light was on they wouldnt be able to plug it into the diagnostic machine, and that i should get it booked in. But as i have just changed my plugs myself and they charge £60 p/hour i want to know the problem before they tell me something i already know!
The car is a MY00 PPP.
I initially put the problem down to the spark plugs causing a misfire, as thats the sensation that was happening.
I have this morning changed my spark plugs (They were long over due and havnt been changed in about a year) The car had NGK6's and after taking them out it was obvious they were no good anymore. I have replaced them with NGK7's and when started up the car did actually sound as though it was starting better.
I then took the car onto the bypass to see if this had cured it. I accellerated slowly and once again at 3-4k it started hesitating. So although i have done some good by replacing the old plugs they werent a cause of the problem, or the main cause anyway.
I have gone all around the engine bay checking all cables wires, hoses etc to ensure they are all connected properly and they all seem fine. The air filter was also cleaned whilst the plugs were changed.
The only things i can think of now are possibly the coil pack and or ignition leads need changing. Ultimatly the ECU may even be at fault but im thinking its one of the former.
Obviously the car isnt any fun to drive at the moment and i would apprieciate any help and advice on the matter. I have been to Subaru and they fobbed me off by saying unless the engine management light was on they wouldnt be able to plug it into the diagnostic machine, and that i should get it booked in. But as i have just changed my plugs myself and they charge £60 p/hour i want to know the problem before they tell me something i already know!
The car is a MY00 PPP.
#3
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Sounds like it could be the maf mate. Do a cell check see here on how to do - http://www.saxonfields.freeserve.co....e.htm#_Sensors
I thinks its the same black plugs on your MY but not sure.
I thinks its the same black plugs on your MY but not sure.
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My car's doing something that sounds very similar, (standard '01 WRX). When I accelerate steadily, not too hard, not too slow it hesitates and stutters sometimes between 2.5k and 3k rpm's. Sometimes it does it again (but less so) at 4k rpm's.
My car's only done 25k miles but is 4 years old so when I spoke to Subaru they suggested that I take it in for it's 30k miles or 36 month service. He told me that the plugs are pretty much shot after 30k miles so I'm hoping that a plugs/filters/fluids/etc change will sort the problem.
I read quite a few posts on this site that suggest cleaning the 'Boost Control Solenoid' so you could try this. Apparently it's easy to do, search the technical forum for 'Boost Control Solenoid' and you'll find fairly detailed instructions and a link to a picture that shows you where the solenoid is, in the engine bay.
I also tried changing my petrol to super-unleaded today, after running it on 95ron for about a month and it was REALLY bad for about 20 miles and then seemed ok. Fingers crossed my service will fix the problem because it's really bugging me.
My car's only done 25k miles but is 4 years old so when I spoke to Subaru they suggested that I take it in for it's 30k miles or 36 month service. He told me that the plugs are pretty much shot after 30k miles so I'm hoping that a plugs/filters/fluids/etc change will sort the problem.
I read quite a few posts on this site that suggest cleaning the 'Boost Control Solenoid' so you could try this. Apparently it's easy to do, search the technical forum for 'Boost Control Solenoid' and you'll find fairly detailed instructions and a link to a picture that shows you where the solenoid is, in the engine bay.
I also tried changing my petrol to super-unleaded today, after running it on 95ron for about a month and it was REALLY bad for about 20 miles and then seemed ok. Fingers crossed my service will fix the problem because it's really bugging me.
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that sounds just like to boost sollenoid had the same problem with mine,as soon as id cleaned it the car was running fine.
get it cleaned mate should only take you about an hour![Big Grin](https://www.scoobynet.com/images/smilies/biggrin.gif)
dannytwo
get it cleaned mate should only take you about an hour
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Originally Posted by Anger
Mines feeling so bad at the moment, i cant be botherd to drive it.
Need to get it sorted, a chump in a 318 bmw beat me of the lights today
Need to get it sorted, a chump in a 318 bmw beat me of the lights today
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Please check ur lamda and maf mate. Yours is like mine was before mine went bang - and that was down to the lamda failing.
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Lamda checked through a diagnostic plug in and ECU read at any Subaru garage. Takes 2 min. Badger em.
Also, your fuel consumption will have dropped if the lamda's gone and you may notice a surging urge when you try to drive at fixed rpm.
Idle is likely to be erratic when the engine's coldish but not always the case.
Also, your fuel consumption will have dropped if the lamda's gone and you may notice a surging urge when you try to drive at fixed rpm.
Idle is likely to be erratic when the engine's coldish but not always the case.
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Marc - I checked my Lambda last week. It is a pig to get a voltmeter on the sensors itself though so take a reading from the ECU itself.
If you dont know where it is it is under the floor of the passenger foot rest - Remove the carpet and remove the relevant bolts which hold it down. Slacken the nuts for the ECU and push a meter into the relevant pin on the ECU - I put the GND under a bolt which held the plate down to get a good Earth.
I am sorry but I cant remember which pin I used - I did a post to ask people if it was the right pin - See if you can find it on the archive - Posted it a week gone friday ago.
Basically the Lambda should read between 0.1 and 0.9 volts and you should see it moving around between the two. People seem to suggest if it is very low or high it is shot. You also need to use a reasonable voltmeter. Although I used a digital some people say an analogue one is more suitable.
If you dont know where it is it is under the floor of the passenger foot rest - Remove the carpet and remove the relevant bolts which hold it down. Slacken the nuts for the ECU and push a meter into the relevant pin on the ECU - I put the GND under a bolt which held the plate down to get a good Earth.
I am sorry but I cant remember which pin I used - I did a post to ask people if it was the right pin - See if you can find it on the archive - Posted it a week gone friday ago.
Basically the Lambda should read between 0.1 and 0.9 volts and you should see it moving around between the two. People seem to suggest if it is very low or high it is shot. You also need to use a reasonable voltmeter. Although I used a digital some people say an analogue one is more suitable.
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Ive had the boost solenoid off (managed to snap the alarm bracket off in the process
) All the hoses off it are clear so there isnt a blockage there. The solenoid itself was squirted through with gt85 and no blockage found there either, it even had compressed air passed through it quite freely. There was also no break in the circuit when tested with a volt meter. But as its a sealed unit there wasnt much more that could be done?
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I went back to Subaru tonight and ive had it plugged into the diagnostic machine. The machine showed up no faults and the readings all appeared normal. I went out in the car with the mechanic driving and he put it down to either the plugs ( which ive just changed ) or the ignition leads. He had 3 back at the garage so im going to swap them over and see if thats the problem!
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Originally Posted by 16vmarc
I went back to Subaru tonight and ive had it plugged into the diagnostic machine. The machine showed up no faults and the readings all appeared normal. I went out in the car with the mechanic driving and he put it down to either the plugs ( which ive just changed ) or the ignition leads. He had 3 back at the garage so im going to swap them over and see if thats the problem!
Did you go to Pulleyns? Found their mechanics to be helpful recently they reset my keypad and programmed a new key for nowt...
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Yeah pulleyns, Kev looked at it. Top bloke.
Ive just changed the leads (there were actually 4 in the bag!). I changed the offside first and took it down the road, still jerking. Changed the other side too and its exactly the same. Ive had the coil pack off too just incase there was anything under it really and its all fine.
So after all this its time to let the garage have a go im afraid.
Ive just changed the leads (there were actually 4 in the bag!). I changed the offside first and took it down the road, still jerking. Changed the other side too and its exactly the same. Ive had the coil pack off too just incase there was anything under it really and its all fine.
So after all this its time to let the garage have a go im afraid.
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Originally Posted by Anger
Mines feeling so bad at the moment, i cant be botherd to drive it.
Need to get it sorted, a chump in a 318 bmw beat me of the lights today
Need to get it sorted, a chump in a 318 bmw beat me of the lights today
Ben
Last edited by ben1413; 01 July 2005 at 08:14 AM.
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Originally Posted by Anger
I cleaned my boost solonoid and it was fine for two weeks and now it seems to be back to how it was before with the turbo coming on and off, any ideas anyone ?
Thanks
Anger
Thanks
Anger
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Booked in for next thursday, £65 an hour
Apparently theyll ring me if they havnt sorted it within the hour!
The exhaust was blowing and the car almost stalling when i let the car idle at the dealers car park, i hadnt put the air hose back on properly when checking the coil pack last night!
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The exhaust was blowing and the car almost stalling when i let the car idle at the dealers car park, i hadnt put the air hose back on properly when checking the coil pack last night!
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£285 later and car fixed!
It was the MAF sensor. Now it may just be me but the car definatly feels faster than it did before! Although ive noticed a bit more lag now. Im wondering how long the old MAF was on its way out for!
It was the MAF sensor. Now it may just be me but the car definatly feels faster than it did before! Although ive noticed a bit more lag now. Im wondering how long the old MAF was on its way out for!
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I've just experienced last night what sounds like the same sort of problem.
99 Uk standard impreza.
Between 3,000 - 5,000 revs from half throttle to full throttle - violent judder - (feels like the fuel line has been cut). Only occurs in gears, 2,3,4,5 - ie not first which I thought was a bit weird. Also only occurs when you can hear the turbo spinning up.
The odd thing is, that it has all of sudden done this without any warning at all. Take for a very spirited run on Friday - fine. Drive it out on saturday - violent judder
I know this thread is fairly self explanatory, but can anyone offer any suggestions as to the most systematic way to resolve the proble - ie it looks like:
1. Replace plugs.
2. Clean boost solenoid.
3. check MAF sensor.
4. refer to garage if all else fails for diagnostic.
Any help would be much appreciated as the car is not pleasant to drive at all.
Cheers
Chris
99 Uk standard impreza.
Between 3,000 - 5,000 revs from half throttle to full throttle - violent judder - (feels like the fuel line has been cut). Only occurs in gears, 2,3,4,5 - ie not first which I thought was a bit weird. Also only occurs when you can hear the turbo spinning up.
The odd thing is, that it has all of sudden done this without any warning at all. Take for a very spirited run on Friday - fine. Drive it out on saturday - violent judder
![Mad](https://www.scoobynet.com/images/smilies/mad.gif)
I know this thread is fairly self explanatory, but can anyone offer any suggestions as to the most systematic way to resolve the proble - ie it looks like:
1. Replace plugs.
2. Clean boost solenoid.
3. check MAF sensor.
4. refer to garage if all else fails for diagnostic.
Any help would be much appreciated as the car is not pleasant to drive at all.
Cheers
Chris
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