[Corsa B 1993-2000] X10XE Poor Running

[BenWilliams21]

So got two issues with the car.

1)

When first starting, it really struggles to start up and needs to have a push from another battery. Normally get mums car and jump start it and then it'll turn first time. Once it's running, it'll stay, not erratic, no warning lights on dash etc. If you then turn it off and restart it, it'll be fine but leave it over night - exactly the same problem. I think this is dodgy battery.... Thoughts?

2)

You have to rev it really slowly to get any speed out of it and work through the box really slow. If you put your foot down to quick the revs are really jumpy and struggles to go over 40. For example, I went out last night and around town, 30mph, it's fine, leave it in 3rd will just cruise - if you then go to put your foot down, the revs are really lumpy and wont pull. Put it in 2nd, it'll go... but again let the revs get too high... it struggles. Hard to explain but if you accelerate easily, not putting too much work on the engine it'll happily get up to 90 and sit there.
Again, I think this is either crank sensor or tps.... Thoughts?

[Taurus]

1. Sounds like the battery isn't holding charge or isn't being fully charged. If you have a multimeter check the battery voltage last thing at night and then first thing in the morning (with the engine off). See if it's dropping. It should hold at 12.5v. Anything much less suggests a dud cell.

Check also with the engine running - should be around 14v.

Remember that an alternator will not fully charge a low battery, it only replaces the charge used when starting the car. So you may need to give it an overnight trickle charge. (The old dynamos used to fully charge a flat battery but alternators don't - a common misconception.)

2. May be due to low voltage (low battery voltage can do funny things to ecu systems), or may be something as simple as old plugs. When was it last serviced - full service, all filters, plugs etc?

[BenWilliams21]

Covered what I thought.

With engine running, battery is 14.9v exactly. Not running, I don't know... not looked.

It's been serviced, checked the plugs last night as obviously I've been trying to start it loads, all nice and silver. Only replaced a month or so ago.

[BenWilliams21]

Wont start at all now, not even being jumped.

New battery fitted, checked the plugs, checked the 2 earths I can see but nothing. Also tried swapping between my 2 coil packs and still nothing.

Loosing so much interest now :/

[Vegas]

Has the new battery got good charge? Sometimes they're left on te shelves for months before selling

[BenWilliams21]

Yep trickle charged it last night. Tried using mums car to jump it.... which is how I've had it running... but even that's not helping now.

Read that earth points can cause the poor running, ie under load, so looked for them this morning but can only see 1 to the drivers side of the scuttle and 1 next to the battery. Taken these off and given a good clean and put back on. Did have a look across the back of the bay as apparantly there should be a big one on there but can't see anything?

[Vegas]

Not sure on your engine, but on the sport and on mine, they're down the back on the bolt for the starter motor, there's one there.

You should be able to test by putting an earth from the block to an earth using jump leads. Although I doubt it's an earth issue, as symptoms started before.

Have you checked for spark from the leads?
If plugs aren't wet, are you sure there's fuel getting to them?

[Taurus]

Is it cranking over?

If it is cranking, then try this - turn the key to no.2 position but do not crank the engine. Then look on the fuel rail and find the valve, usually covered with a black cap. Press the pin in the valve and see if petrol spurts out (so be careful!). If not tell us.

If petrol does spurt out then get back in the car and crank it over - for say 5 seconds - then repeat the check on the fuel rail valve to see if fuel pressure is still present.

There's a number of things it could be, so do them one at a time.

[BenWilliams21]

Yes it's cranking over.

Well I took the plugs out the other night, they were clean, no black etc but did feel wet to touch....?

Will try the earth with jump lead when it stops raining, along with fuel rail

[BenWilliams21]

Tried the earth - no difference

Tested the rail with ignition on 11, sprays loads out in a nice jet

Next?

[Taurus]

Tried the earth - no difference

Tested the rail with ignition on 11, sprays loads out in a nice jet

Next?

OK there's fuel pressure before cranking, which is the fuel pump priming run. Did you do the next thing as per above - ie then crank it over and repeat the check for fuel pressure?

The point being that you get a priming run when you first turn the key, the fuel pump relay then cuts out until the ECU senses the engine turning. If the relay operates then you get fuel pressure on cranking. If not then there's no fuel pressure. Usual suspect is the crankshaft sensor.

If there IS fuel pressure on cranking the next test is if it is actually getting into the cylinders - you need to see wet plugs. If there is pressure at the rail but the plugs are dry then check the fuel injector relay.

[BenWilliams21]

Yep sprays on crank as well, and plugs are wet Which surely then means no spark?

I've swapped the coil pack already for a known working one...

[Vegas]

Test to see how strong the spark is, out a spark plug in the end of ht lead and hold the ht lead with some insulting pliers. See how stron the spark is

[BenWilliams21]

How can I do that with a coil pack though? It's all one sealed unit?

or am I being thick?

[tanktop]

You can push the spark plug into the rubber protector sleeve and earth it on metal