Vauxhall Corsa-C Forum banner
1 - 12 of 12 Posts

·
Registered
Joined
·
7 Posts
Discussion Starter · #1 ·
Hi all,
Just joined as this seems to be a great place for advice.
I have a 2003 combo 1.7 di ex Royal Mail van.
It starts bang on the key every time, but shortly after runs really rough and cuts out. It starts again fine but then does the same thing. There is also some white/grey smoke initially, which smells like diesel.
When it's on the move, it seems ok and doesn't miss a beat.
Also, when at a standstill while it's idling rough, pressing the accelerator has no effect of pick up, but if you catch it before it starts running rough, it'll sit and hold anywhere in the rev range.
Sorry for tge rambling, but just trying to note everything I'm experiencing.
Just can't fathom it.

Any help would be so very much appreciated, as this is for my work so am stuck without it.

Many thanks

Lee
 

·
Registered
Joined
·
2,830 Posts
How "shortly" does it start running rough? Long enough to really get up to temperature, or within seconds or a few minutes? If it's fine for a while, there may be something wrong with the MAF. I'm not particularly (as in not at all) mech, but I do read around the contributions of the better minds here. IIRC, if a MAF is dodgy the engine will run by default as though cold so, initially, you won't get much difference until the engine warms up and then you'd get wrong fuel/air ratios. That doesn't tie in with the no response to the accelerator (poor acceleration, yes, but no response at all seems extreme). The thing is, Corsas and Combos seem to be very picky about having a Bosch MAF, so buying a cheap replacement doesn't tell you much as it could easily be just as duff, and a new Bosch is a pricey thing to buy on a hunch. A used Bosch for the 1.7 Di/DTi can be found on ebay around £15 and might be worth thinking about if the free checks don't point elsewhere.

If the rough running happens really soon after starting up, you might be running on less than four cylinders. Removing an injector at a time would be a pointer; if pulling one out makes no difference but pulling out any of the others makes it practically die on its buttocks, you've identified the non-firer and it might be that injector which, I'm pretty sure, doesn't have to be programmed when replaced. The crank sensor could cause rough running, but I'd expect at least some difficult starts which you don't seem to be getting. The other possible that occurs to me is the EDU, which is the brains of the diesel delivery. Again, these don't have to be programmed when replaced (plug and play) and they can be a common fail for the Di/DTi which, for these two reasons, makes them an expensive used part. They tend to sell or fetch in an auction around £70, so another thing not to be bought on a hunch.

Sorry I don't have a fix, just throwing possibles against the wall to see if something sticks, but there are a few 1.7 owners here who are handier with spanners than I am and they will be more useful to you. It would help if you could define how long it runs smoothly and also check for any codes the car gives you, then post them here. There is a pedal test that saves you buying some generic code reader
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #5 ·
How "shortly" does it start running rough? Long enough to really get up to temperature, or within seconds or a few minutes? If it's fine for a while, there may be something wrong with the MAF. I'm not particularly (as in not at all) mech, but I do read around the contributions of the better minds here. IIRC, if a MAF is dodgy the engine will run by default as though cold so, initially, you won't get much difference until the engine warms up and then you'd get wrong fuel/air ratios. That doesn't tie in with the no response to the accelerator (poor acceleration, yes, but no response at all seems extreme). The thing is, Corsas and Combos seem to be very picky about having a Bosch MAF, so buying a cheap replacement doesn't tell you much as it could easily be just as duff, and a new Bosch is a pricey thing to buy on a hunch. A used Bosch for the 1.7 Di/DTi can be found on ebay around £15 and might be worth thinking about if the free checks don't point elsewhere.

If the rough running happens really soon after starting up, you might be running on less than four cylinders. Removing an injector at a time would be a pointer; if pulling one out makes no difference but pulling out any of the others makes it practically die on its buttocks, you've identified the non-firer and it might be that injector which, I'm pretty sure, doesn't have to be programmed when replaced. The crank sensor could cause rough running, but I'd expect at least some difficult starts which you don't seem to be getting. The other possible that occurs to me is the EDU, which is the brains of the diesel delivery. Again, these don't have to be programmed when replaced (plug and play) and they can be a common fail for the Di/DTi which, for these two reasons, makes them an expensive used part. They tend to sell or fetch in an auction around £70, so another thing not to be bought on a hunch.

Sorry I don't have a fix, just throwing possibles against the wall to see if something sticks, but there are a few 1.7 owners here who are handier with spanners than I am and they will be more useful to you. It would help if you could define how long it runs smoothly and also check for any codes the car gives you, then post them here. There is a pedal test that saves you buying some generic code reader
Thanks very much for that. I'll do the pedal test and see what we get.
It only runs sweet after initial startup after for a few seconds before it starts dancing. Smells badly of diesel during and after too.
Lee
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #6 ·
Morning,

Did the pedal test and have the following codes:
0105 MAP circuit
0335 Crank position sensor A circuit.

Cheers
 

·
Registered
Joined
·
2,830 Posts
Okay, that (to my surprise) is not far off my thinking. I didn't know that the Di has a MAF and MAP (thought it was a CDTi thing but the Di/DTi might be MAF only). If your manifold air pressure sensor is duff, that would lead to rough running and also the smell of diesel because it could be giving you a fuel-rich mixture from bad info coming from the sensor. The crank sensor, if duff, can also give you the rough running but as I said before, I would've expected some bad starting which is not your experience.

If you have time and ability, not keen to spend money buying replacements that might not solve the issue (fault codes are great, but not always pinpointing the exact problems. For instance, and I hope not, you could have an ECU problem that's garbling perfectly good info from the two sensors) then initially you might only need to spend on a can of electrical contact cleaner. Google should help you locate the usual suspects, and you could get some useful info from a multimeter and Google to see if the expected numbers are there (and visually you can check for corrosion, broken pins and the like).

I don't know how long and tricky dismantling some of these are so there may be a cost benefit in having a replacement ready but a clean should tell you if there's an improvement. Also, if you disconnect the battery, that will clear the codes (you need to know your radio code, assuming it's a CDR2005 or a lower-spec similar, rather than the later CD30) and if the problem isn't fixed the code will return. Given the time, inspect and clean the MAP, crank sensor (seeing as those are the codes) and do the same for the MAF and EGR because they're well worth a look and the EGR in partic can clog up and cause all sort of running issues.

A bit daunting for me, tbh, but practically free except in time. As it's your work van, time is money but firing parts at it can build up the cost and possibly not fix the problem. If you do replace, go for OE parts and lookout for fakes if they seem suspiciously cheap as I've lost count of "it can't be the sensor because I replaced that last week" posts and it turns out to be the sensor after all, because it was £12 off ebay or the motor factors.
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #8 ·
Okay, that (to my surprise) is not far off my thinking. I didn't know that the Di has a MAF and MAP (thought it was a CDTi thing but the Di/DTi might be MAF only). If your manifold air pressure sensor is duff, that would lead to rough running and also the smell of diesel because it could be giving you a fuel-rich mixture from bad info coming from the sensor. The crank sensor, if duff, can also give you the rough running but as I said before, I would've expected some bad starting which is not your experience.

If you have time and ability, not keen to spend money buying replacements that might not solve the issue (fault codes are great, but not always pinpointing the exact problems. For instance, and I hope not, you could have an ECU problem that's garbling perfectly good info from the two sensors) then initially you might only need to spend on a can of electrical contact cleaner. Google should help you locate the usual suspects, and you could get some useful info from a multimeter and Google to see if the expected numbers are there (and visually you can check for corrosion, broken pins and the like).

I don't know how long and tricky dismantling some of these are so there may be a cost benefit in having a replacement ready but a clean should tell you if there's an improvement. Also, if you disconnect the battery, that will clear the codes (you need to know your radio code, assuming it's a CDR2005 or a lower-spec similar, rather than the later CD30) and if the problem isn't fixed the code will return. Given the time, inspect and clean the MAP, crank sensor (seeing as those are the codes) and do the same for the MAF and EGR because they're well worth a look and the EGR in partic can clog up and cause all sort of running issues.

A bit daunting for me, tbh, but practically free except in time. As it's your work van, time is money but firing parts at it can build up the cost and possibly not fix the problem. If you do replace, go for OE parts and lookout for fakes if they seem suspiciously cheap as I've lost count of "it can't be the sensor because I replaced that last week" posts and it turns out to be the sensor after all, because it was £12 off ebay or the motor factors.
Mate you're a star! I should've thought about the MAP sensor to be honest, as I've had one go on another car not too long back and it gave the same results🤦‍♂️
I'll get my tester out and start having a poke around.
Thanks again for all the help.
I'll post my findings👍
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #9 ·
Right then.
Replaced MAP sensor as voltage not changing at all. Code cleared and checked again.
Started and ran perfectly for 30 seconds, as like a new engine. No blips, no hesitation revs spot on.....then back to sounding like it was running on 2 cylinders and shaking. Rich smelling white smoke came back too.

Code has gone for the MAP still, but still showing P0335 for the crank sensor which just doesn't make sense to me. Does the ecu only reference the crank sensor after startup on these engines, as I thought it needed it from the get go?
Also, am I still having fueling problems due to dodgy EDU?
Looks like it's in a fun place to get too on the back of the engine. 😭

Cheers
 

·
Registered
Joined
·
7 Posts
Discussion Starter · #10 ·
Update:
Van has been butchered. There are so many wiring hacks, things missing, rounded/cross threaded bolts, that I can't spend any more money and time on it.

So I'd just like to say a very big thanks for the pointers and assistance. I was greatly appreciated.

All the best
 

·
Registered
Joined
·
620 Posts
Just by reading the beginning of the post it is already clear kids, an injector fails, you have an injector that the needle does not seal well and is throwing diesel into the chamber at the wrong time, that's why you get diesel without burning through the exhaust, grayish color, and But if it smells like diesel, check all of them since they have no return, I would start with 4 since it is the cylinder that suffers the most in all engines, the idle will have it bad for the rpm, but it will go more as it leaks more , I think I remember that these injectors had a breakdown of the needles, as the engine fails more the engine will shake when accelerating like a tractor losing performance, nl it is good to walk like this since if it burns badly you can pierce the piston
 

·
Registered
Joined
·
2,830 Posts
Sorry to hear that, 0321. From your description, it sounds like there could be so many things to chase down over time, even if the most obvious issue got cleared up. It could turn out to be a vehicle that you're always driving with crossed fingers and sorting at weekends and you don't want that from a works van. The Combo 1.7 Di and DTi are normally pretty reliable, understressed workhorses (one of the reasons why I got mine, to take me to Malaga and back which it does drama-free) but anything can be bodged by a previous into submission.
 
1 - 12 of 12 Posts
Top