Corsa c problems

[bazzap8389]

I'm posting this for a friend as he isn't on any car forums hopefully someone can help.

He has a corsa c 1.4 Sri and the car doesn't rev past 5k rpm, it's as though it's bouncing off the limiter also it takes longer to start then usual.

He was told to change the coil pack and plugs which he has done and it's still the same.

Any ideas? Cheers

[mowgli]

get it plugged in somewhere for a diagnostic check, it sounds like a sensor is out, either that, or the cambelt has slipped

[bazzap8389]

Thanks for the reply il let him know :thumb:

[Will F]

get it plugged in somewhere for a diagnostic check, it sounds like a sensor is out, either that, or the cambelt has slipped
Cambelt?? If that had slipped, it would run like a bag of nails and would probably still rev to the limiter! It's in limp mode so it's an electrical fault. You can flas the fault codes by holding the clutch and brake on and switch the ignition or something... Get that down if you can't afford the diag machine

[phazer]

Crank sensor fault will give this symptom. Check the wiring and the plug condition first before replacing.

[staggy_gsi]

Mowgli could still be right, if its only jumped a tooth or two it could have the same symptoms as a knackered crank sensor. Not as likely as the sensor itself being at fault, but not a stupid suggestion by any means...

[meritlover]

most often on the 16v engines, the sintered crank pulley slips on the woodruf key by a few degrees causing the sync sensor on the cam not to line up with what the ecu expects to see on the crank. everything appears normal from the outside. even the markings on all 3 pullies line up until you remove the bolt and see that its chewed.

check and recheck all the usual.stuff first though, before jumping to any rash conclusions.

happy Saturday

[Will F]

Never heard that on the later lumps. If that were the case, I would have thought that as soon as the woodruff key has been breached, it's game over quite quickly...?

[bazzap8389]

Thanks for the help, the car is booked in for after new year so I'll let you's know what the problem is :thumb:

[meritlover]

Never heard that on the later lumps. If that were the case, I would have thought that as soon as the woodruff key has been breached, it's game over quite quickly...?

No. everything retards by a few degrees so valves are lucky. but its close. problem starts as poor performance which degrades over time until symptoms similar to the above occur.

if the timing was advanced by the same amount it would likely be a different story however.

[Will F]

No. everything retards by a few degrees so valves are lucky. but its close. problem starts as poor performance which degrades over time until symptoms similar to the above occur.

if the timing was advanced by the same amount it would likely be a different story however.

Still not convinced. What causes the slippage to stop further damage? Like I said, once the woodruff has bid farewell, I would assume its game over?

[meritlover]

Still not convinced. What causes the slippage to stop further damage? Like I said, once the woodruff has bid farewell, I would assume its game over?

im not going to sit and convince you that it happens. As ive seen it. Twice. the woodruff key doesnt fail, the sintered pulley does. it chews the keyway a few degrees and then binds up. there is no doubt it would give way eventually as its likely moved because the bolt wasnt sufficiantly tightened. but as the engine will very much be under performing, it doesnt get the chance to.
they purposly use a sintered pulley as a sacraficial element to protect the crank and the machined key. but they are soft as week old bananas.
mostly happens on the 1600s where there is AC and PAS pumps being driven from it as well.

[therealnovaboy]

meritlover you do not get a 1600 corsa C. Other than the s1600 big block.

I have had this happen on a corsa B 1600 and you are correct. The edge of the key on the pully cracks off and forces it around the keyway a bit. It then Jams there with the timing out a couple of degrees. I have pics of mine when it happened.

Im sure the later corsa C engines IE the twinport 1.4 ect are different cranks.

my guess would be the crank sensor. If its taking longer to start its could be because it has to use the cam sensor to find top dead centre. if its only reving to 5K it either cant find a true TDC or its in safe mode.

[meritlover]

Ah yes. Not only are the cranks different but the engines arent even the same. lol

I guess more people should have twigged when I was talking about belts and not chains.

Check the cam and crank sensors then. Same principles. If the sync signal is lost it will give similar issues. So will AFM. It won't be too complicated. There's not much on those engines. Better to get a shot of an OBDII tool to save wasted time and effort.

Happy Birthday Jesus.

[bazzap8389]

My mate got his car back from the garage today, it was the crank shaft sensor. Good shout guys!

[phazer]

:thumb: :d