1.9 loos of power - help needed please.

[Mugs]

hi all,

i have a 1997 1.9 auto Z3 that seems to have a power problem.
i am working 2-10 shift and decided to take the Z3 to work today as the sun was out. it performed faultlessly on the way in but i did notice the kickdown didn't seem as powerful as normal?
on the way home i went via the motorway and it seemed ok but after 10 mins i went to accelerate a bit and it just seemed to decelerate.
i limped onto the A road and decided to unplug my new MAF in case this was the problem. it seemed a little better but not much (apart from the CEL being thrown) so i drove a mile then plugged the MAF back in. again it seemed a little better but still not right.
i got home and it ticked over fine as i was putting it back in the garage but the cat is rattling away.
i know it's not a lot of info and i haven't has a chance to have a look at it but has anyone had similar experience with the 1.9?
thanks in advance.

[BonBon]

Have the codes read. Could be a cam sensor.

[BladeRunner919]

the cat is rattling away.

Blocked/damaged cat would be the obvious solution.

[Del]

I agree with Bladerunner - the cat shouldn't rattle - they break up with age and can cause a blockage.

[Rafolian]

1.9 Loos of power, maybe it just needs flushing?

[Daz3]

My cat was rattling in my 2.8 the asc light kept illuminating and the car was really hesitant on the power and didn't want to accelerate. I removed the cat which when I gave it a shake it rattled like a maraca. Never had any problems since. If you have a code reader handy worth putting it on to see what it brings up!
I've now replaced with one of these

[Bonzo]

1.9 Loos of power, maybe it just needs flushing?

Yeah, then get a 2.8

[Mac The Tank]

Get a code reader; I use one of these

Only cost <£10 off fleabay

with the Torque app for Android
http://torque-bhp.com/

But you can also use a laptop I believe too.

[Mugs]

thanks all.

i have read the error codes and it came up with:
MAF, intake temp, missfire cyl 3, missfire cyl 4, random missfire.
i will replace the cat but i think looking at the codes it could be the coil pack / leads breaking down combined with the cat.
does this sound right?

ps, i tried flushing but it didn't work and i also tried next doors cat but it kept running off

[BladeRunner919]

I'd satisfy yourself 100% that it can't be an air leak before you start swapping coil packs (unless you can find a local member that has the same car and could let you try their coil pack).

[Mugs]

sorrry, i should have said that i have checked for air leaks and the MAF / intake temp flagged up on the ecu as i disconnected them to check they were not at fault (plus it is a new MAF)
i have done some searching and it seems the coil pack / leads can cause this and it is (apparently) very common on the 1.9 engine?

[Del]

I've not heard of the M44/M43 engine HT leads being a weakness. I spoke to an ex-BMW master tech a few years ago and he said that he'd never had to replace a set, as the original Bremi ones were very high quality. You can put a multimeter at the two ends of each lead to measure their resistance, it should be around 5 to 5.5 kohms (varies slightly with length) - anything significantly more than this and you have a problem.

It might be worth plugging back-in the MAF, deleting those existing ECU errors, run the car and then take a fresh, new error code reading. There have been one or two instances (on this forum) of the coil packs failing on the M43/M44 engines, which gives the generic cylinder misfire readings you have. But again, as the pack is situated away from engine heat and vibration it tends to be quite reliable.

The problem when a Cat breaks up is that pieces travel down the exhaust and can cause an obstruction. If you replace just the Cat section you will need to remove the rear section and shake out any loose pieces otherwise you may have an on-going problem.

[BladeRunner919]

I do think that you should replace the cat before you spend any other money - you have to replace it anyway, so you may as well start there.