Vauxhall Corsa - Lack of Power/Gutless

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Wed 12 Oct 2011 14:40
Vauxhall Corsa - Lack of Power/Gutless - Flakeydave

I need help as I cannot find what’s wrong with my car it barely revs above 3000 rpm when under load or when driving although it revs to the limit when static, exhaust burns clean no excessive smoke or any noises from the engine, is very economical returning 55 mpg, It will only do 85mph downhill with the wind behind it. It is the Y17DTL engine with no air charger. I bought the car without road testing it and the guy refused to take it back saying it was sold as seen so I have no history of why this fault exists. I will list everything I have done to date so perhaps you can suggest some ideas!

1. Engine flushed and new oil air and fuel filters, removed the pick-up unit in the fuel tank and cleaned the plastic gauze (although not dirty and the bottom of the fuel tank was clean) siphoned fuel out at the filter head to confirm clear fuel feed to filter.

2. Took the exhaust manifold and turbo off as one unit to check that the turbo was not seized and rotated freely, I also wanted to check that the vacuum unit to the turbo boost and its linkage was not seized. All ok

3. I left the exhaust down pipe off at the manifold and took for a drive to eliminate any blockage in the exhaust system. All ok

4. Checked the cam belt timing to confirm it was not a tooth out. All ok

5. Changed the MAF sensor with the one on my daughters Vauxhall Vectra as it was the same Bosch unit which had the same part number. This made no difference.

6. I removed the EGR valve unit and gave it a good clean out with carb cleaner and elbow grease although it was not really very dirty. No difference.

7. I went to a local scrap yard who allowed me to change the MAP sensor and the EGR control unit before I buy. This made no difference no guaranties these were ok.

8. Removed the rocker cover and checked the valve clearances, some were at 30 thou, some at 35 thou and only 3 valves at the correct 40 thou although I do not believe this to be the fault.

9. I called a Company that repair the EDU units fitted at the back of the sump, they say my fault is unlikely to be the EDU unit (Will not start of cuts out is normal faults) and that I would be wasting my money to get this checked.

10. I took the car to garage, Hickleys of Taunton in Somerset who are specialists, the technician spent 3 hours on the car but was unable to find any faults this is what the report said :-

Found no DTC’s. No air leaks found, exhaust is not blocked, turbo is boosting correctly, Air flow meter correct, timing correct. No contamination found, Pump seeks ok. EGR is operating however block of EGR to try to improve performance, car is running better, advise customer to try and return if not happy.

11. The Technician suggested it could be the ECU, the fuel pump or maybe the injectors. I found a guy on eBay that re-programmes second hand ECU’s to your car at £200 and as I described the fault he thought that it was the ECU at fault and would change it and if this was not the fault he would only charge £50 for the visit and re-programming. He came down to Yeovil from London and spent over 2 hours with me and the car, it is not the ECU. He got me to hold his diagnostic equipment whilst he drove the car and said the turbo boost fault flashed up temporarily and so he spent a long time trying to locate the fault but to no avail, he suggests that the Vacuum pump is weak and not giving enough vacuum to control the turbo boost correctly.

12. I remove the alternator and stripped the Vacuum pump off and took it apart, it is a cylindrical vain pump but I could see no signs of wear, the cylinder was smooth and un-scored the carbon type brushes were clean no signs of scoring or scratches and looked unworn. I lightly greased it and put it back but of course that made no difference.

13. I bought a second hand fuel pump from a 2004 car that had only done 46,000 miles as the bottom end was knocking after running out of engine oil.

14. I have now ordered new vacuum hoses for the EGR and boost control valves and the hose to the boost unit in case these are collapsing internally.

I really am out of ideas now!

Please help!!!

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Wed 12 Oct 2011 14:48
Vauxhall Corsa - Lack of Power/Gutless - tdc

What a list!Did it include compression check,binding brakes?Can you hear/feel turbo kicking in/spinning up?

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Wed 12 Oct 2011 15:31
Vauxhall Corsa - Lack of Power/Gutless - bathtub tom

It could almost be a slack throttle cable, but I assume it's got a throttle position sensor.

Have you checked for correct operation?

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Fri 14 Oct 2011 11:06
Vauxhall Corsa - Lack of Power/Gutless - Flakeydave

Its an electronic control by throttle position sensor, Hickleys the garage should have checked this, it will rev to 5500 rpm when run up on the drive but I feel its slow to pick up.

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Fri 14 Oct 2011 11:04
Vauxhall Corsa - Lack of Power/Gutless - Flakeydave

Yes Hickleys did a compression check and said that they were all ok although I was not given the figures, no i can't hear the turbo kicking in but I took the air pipe to the manifold off and reved it up and got high pressue, then put it back on without tightening the jubilee click up and drove it again, the pressuse blew the rubber connect off the pipe so I guess it was high pressure. As metioned in first post, I took the turbo off and it spins freely.

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Mon 24 Oct 2011 17:07
Vauxhall Corsa - Lack of Power/Gutless - roosterbooster

try cleaning out the fuel injectors have come across combo vans with same symptons take injectors to deisel specialist for check/overhaul

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Thu 13 Oct 2011 04:34
Vauxhall Corsa - Lack of Power/Gutless - 1litregolfeater

Sounds like you've done everything I would have, and then some more. But then I'm clueless when it comes to diesels. The missus has a Y17DT in her Astra, which has popped up codes recently, which seem to have gone away, they were:

P0370 - Pump Position Sensor Invalid Signal
(04) - Not present

P0400 - Critical system malfunction 1 (refer to checking procedure: trouble code description)
(03) - Present

But like I say, they went away. Did a quick search at the time and the consensus seemed to be to clean the egr.

Keeping fingers crossed as after 80,000 miles I've never needed to take it apart. Wouldn't know what bit is what.

I can tell you these Isuzu engines are very complicated and have numerous sensors, but you know that already.

So - do you have any engine management codes?

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Thu 13 Oct 2011 04:57
Vauxhall Corsa - Lack of Power/Gutless - 1litregolfeater

Thinking about it, you need to take someone out for a drive, with a laptop and a diagnostic unit like op-com plugged in. Hopefully someone able to understand what it means while the car is accelerating.

Somebody skilled should be able to work out, what's going on.

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Fri 14 Oct 2011 11:10
Vauxhall Corsa - Lack of Power/Gutless - Flakeydave

Hi sounds good, do you know anyone who can do this thats not going to cost me an arm and a leg? I live in Yeovil

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Fri 14 Oct 2011 11:08
Vauxhall Corsa - Lack of Power/Gutless - Flakeydave

There are no management codes and no illuminated management light, my RAC man also plugged his unit in and says there are no codes.

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Sat 15 Oct 2011 03:37
Vauxhall Corsa - Lack of Power/Gutless - 1litregolfeater

I'm in Lancashire, so a bit too far to pop round.

With engine diagnostics, you always need to be imaginative, and think laterally. So your lack of codes is helful in itself, it indicates that all measured functions are within pre-designed parameters.

So all the sensors must be ok, and those components measured direstly by those sensors must be ok, we must suppose.

I'd revisit or at least put in the back of my mind, again, low compression and dodgy injectors, but I know you've been there done that. Or an electical fault, which leads us back to the ecu.

Ecu will be fine but you may have poor earths, poor connections in the fuse box and anywhere there is a connection, and anywhere a wire could be cut or shorted. Do you need a new battery.

A leak in a a vacuum line will cause the symptoms in a petrol car, I didn't know diesels had um. let us know how it goes. I do know there's some kind of unit, at the back of the engine. above the exhaust with lines going to it, because when I was down there waxoyling I thought "I hope this doesn't go wrong". No idea what it is

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Sat 22 Oct 2011 11:34
Vauxhall Corsa - Lack of Power/Gutless - Flakeydave

Checked and cleaned all earth cables but still the same, the vacuum serves the servo to the brakes and both the EGR valve vacuum unit and the turbo waste gate vacuum unit these are of course controled by signals from the ECU to a solenoid to activate them.

The unit to the back of the sump is the EDU unit which controls the spill valve in the fuel pump, I have checked with a company that overhauls these units who say the fault I am descibing is not related to this it would not start or would cut out at idle are the only 2 faults related to the EDU.

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Sun 14 Oct 2012 01:28
Vauxhall Corsa - Lack of Power/Gutless - Harryg1991

Hi Flakey Dave. My combo is suffering the exact same problem and have tried most of the things you have, I am now going crazy trying to figure this out. Did you ever sort the problem out with yours? Anyone else have idea's please, I going mental here hahah

Cheers Harry

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Fri 9 Nov 2012 10:26
Vauxhall Corsa - Lack of Power/Gutless - corsa diesle dieing

My Corsa is doing the exact same thing, it is sooo anoying.

However mine started happening straight after the fule pump dided oneday like in an instant, took it to the garrage and had a new fule pump fited however its been as you have described since.

I have been working with my mechanic friend since and found no joy.

Am begining to think that the injectors may be slightly blocked,

Did you ever suss the problem?

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Sat 10 Nov 2012 03:27
Vauxhall Corsa - Lack of Power/Gutless - 1litregolfeater

No fix here, but this is proving an interesting read. As no common fault is present, maybe these engines are just wearing out.

I do know that mine suffers from dilution of the oil from diesel leakage, over a year or thousands of miles. I've used synthetic Comma 5/40 for 6 years. It goes black and thin alamingly quickly.

So maybe the fix is change the oil as frequently as you want to afford it, and possibly a heavier version?

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Mon 12 Nov 2012 08:15
Vauxhall Corsa - Lack of Power/Gutless - corsa diesle dieing

Right Ive sused it!

After trying most things, found that it was a rubbr seal on the inlet to the turbo that had been installed incorectly and ad was restricting the air flow.

I had the exact symptoms you had and found that if you take the inlet off the turbo and rev it you should feel it sucking, if it works fine without the turbo inlet pipe on its more han likely a blockage somwhere in your air flow pipes or blocked air filter.

all the best.

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