Engine code Y17DTL
Yesterday, car suddenly lost what grunt it had and is now quite hesitant/underpowered and sometimes gives out a lot of grey smoke.
I tried to invoke the EML, which I succeeded only at 3500 rpm. I don't know what it says yet as the scanner is in the car but the software's at home! Only a cheap code reader one so don't get too excited yet about live data.
It barely made 70mph on the dual carriageway with my foot flat to the floor.
I can hear the turbo winding down when turning off and no whining noises presented from it previously. The car idles fine with no cutting out or mis-fire.
My initial guess is EGR, with what looks like a vacuum-operated valve connected via a solenoid. Problem is it's all hard-plumbed into the turbo tract so I can't easily block off the pipe from the exhaust manifold.
Any suggestions much appreciated.
Edited by mfarrow on 25/08/2008 at 22:32
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Mike
The code will help; have you also got a vacuum gauge available?
EGR is usually black smoke - but....
A blocked tailpipe is another possibility.
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Screwloose
I have a vacuum gauge. What should I be testing?
Girlfriend drove it yesterday back from taking me to the station (4 miles). She says car was barely driveable on the way home and even difficult to get going at junctions, and very slow.
Smoke was definitely grey when it left the station.
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Plug your vacuum gauge straight into the outlet of the vacuum pump and see what the vac level is at tickover. Then reconned the pipe and tap-in somewhere else to see what it is then?
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I assume the only pump is the one on the back of the alternator and that we're trying to establish if it's working right and if there are any vacuum leaks?
I'll have a look at it on Saturday when I'm back up there. How would I know if the exhaust is blocked? Bang on it?
Thanks, Mike.
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Mike
I was thinking of the later cam-driven pump; on that type, just confirm that there is good vacuum [21in+] feeding the solenoid.
If the exhaust has collapsed internally; the gases are hot and slow coming out.
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Hi there
Sorry for the long post, but I have some data for you.
Vacuum at the solenoid hose T-piece (there's a blanking plug you hook into) is 26.5 inches of mercury. The exhaust gasses at idle are hot when the engine's hot but are plentiful and pulsating as they should.
The fault code I think you're after is P1125 (5). I did get another one after I unplugged the electrical connection from the solenoid but I'm assuming this is self-induced (P0400).
I managed to induce P1125 (5) again up a hill at 3000rpm in second gear (this is the fastest it would rev.)
I got it home after approximately 8 miles and saw that I had some live data (!!!) in the 'better' free software I downloaded this morning. These showed for battery fine (12.3V un-started, 13.8V throughout rev range); accelerator position sensing correctly; spill-valve relay constant active; main relay active; simulated full load switch only seems to deactivate when decelerating; coolant 93 Celsius; air intake 24 Celsius.
Now the important stuff. The boost doesn't go above 113kPa at 3000rpm (max engine speed). Drops from ~107-110 to ~103-105 when accelerating, accompanied by dip in engine power (happens approximately 1 second after pressing accelerator).
All MAF values were taken at a standstill.
At home and stationary MAF read 32.5kg/h @ 850rpm; 58kg/h @ 2000rpm.
When driven for approximately 10 miles the car is a lot worse (as my gf found on Monday). It gets to a point where there is hardly any power at all, in any gear, or any engine speed. This is when the values change considerably.
The MAF now reads 28kg/h @ 2000rpm. There is now no steady increase in engine speed when stationary (it likes to rest at 1800rpm) until your foot slowly goes to a recorded ~80% throttle position, at which point there is a click accompanied by a sudden surge to 3000rpm; ploom of grey/white smoke; and approximately 80kg/h air intake @ 3000rpm.
I think I've got the car to a drivable state by taking the electrical connection off the EGR solenoid. The smoke has stopped, but it is still lifeless and doesn't have the surge of power over 2000rpm like it should.
I hope that's enough to go by.
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Mike
Lots to go on there - some of it plain odd? At least the vac level is good.
P1125 is wastegate control solenoid - circuit malfunction. Check the resistance of the solenoid is 5 Ohms. They may be swappable with the EGR one - check numbers.
[The P0400 - critical system malfunction - code is indeed EGR related.]
Those MAF values are way low. I'd expect 300+ kg/h when blipped hard.
Either your MAF is toast; or you do have a flow restriction.
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Screwloose
P1125 is wastegate control solenoid - circuit malfunction.
I can't seem to find that solenoid (would it be along the wastegate vacuum pipe?) though it is listed in Haynes.
The EGR solenoid read 16.2 ohms.
I'll have another go with the MAF readings now my laptop has charged up.
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Mike
I'm really struggling with a failing memory now; but I've a feeling that it's down the back of the engine, cam-belt end.
15-ish Ohms seems much more like it. AD may be wrong.
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No problem Screwloose - seems you're spot on as it was at the back of the engine mounted on the injection pump.
I took both solenoids off and they each showed 16 ohms, and actuated with 12V applied across the terminals. They each have a different part number, so I've replaced them as they were.
I've had a quick google search on the P1125 and came up with this page www.ilexa.co.uk/forum/index.php?action=printpage;t...0 . Correlates with what the scanner told me (critical circuit malfunction 2).
Got the computer back on it again and read a MAF reading of 20kg/h at idle. This time it's even worse, in that the engine speed dips at idle on roughly a 2 second cycle, and nearly stalls.
So I took the exhaust off. What a difference! Revved freely with steady idle and came up with the following MAF readings:
35kg/h @ 850rpm
80kg/h @ 2000rpm
230kg/h @ 3000rpm
>300kg/h when throttle blipped up to circa 4000rpm
The boost pressure is a lot better now too. I've seen it go into the 135s and roughly match the command values.
So, I think blocked exhaust it is! I don't know whether to replace the whole thing (i.e. +cat) or just the back box. The cat is only 2 years old and 20k miles at most, but I think the back box might be original. What are the chances of a cat going after such a relatively short time? I tried to separate the two but have only rudimentary tools here at gf?s house, so I couldn't even drill holes before the back box (which I'll replace anyway) to rule out the cat. You can only think to bring so much!
Edited by mfarrow on 30/08/2008 at 22:45
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Mike
Diesel cats can clog quite quickly; if it's that, gut it with an iron bar. Waste of space and weight
Astra tailpipes can collapse internally; run a rod up it and see if it's clear.
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Screwloose
You were right about the catalyst. Had to demolish the back box off anyway to separate them; as I don't have the correct tool to do this properly, only an angle grinder.
To my disappointment it was still the same, so rammed the guts out of the cat (honeycomb seemed to be blocked with fluff ???) and all is well again.
Thank you Screwloose, I couldn't have done this without your help.
Edited by mfarrow on 07/09/2008 at 22:17
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Mike
Glad to have provided a few pointers.
Blocked with fluff eh? Have you seen the neighbour's cat lately?
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GF's neighbour's cats have all been inherited by them, so I don't think it's that.
It's white (now black) cotton-like fluff which came out in clumps at first so I assumed was part of the cat, but then I saw it stuck to the face of the monolith. Odd.
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