Manta Gt/e No Power Up To About 3000Rpm?

[85_GT/E]

Hi I have been spending the last 7 weekends welding my Manta ready for the MOT last Saturday, well the good news it passed but the bad news is up to about 3k the is no power at all and it pops back through the exhaust every now and again, when it is ticking over it revs up fine it seems to be when the engine is put under load.

When it went for MOT the tester said the emissions where that low it would have passed an cat test don't no if this has anything to do with the no power fault?????

Thanks for the help i was given on my last question, when i bought the car it would start up straight up first time but would tick over the person who mentioned the servo pipe were spot on i pulled the pipe off the injection manifold and put my finger over the hole and it ticks over sweet as a nut i have since replaced the pipe.

I just need to sort this now, so i will be ready for billing carnt wait !!!!! is there any help any one can give please????????

I have posted a few pics to show you my new Manta.

[manta400john]

Is it lack of power or a missfire? When you say under load that would suggest it's a missfire..?

I assume you've not been using it in between your weekend welding sessions....so what if maybe the flap in the air flow meter was sticking?...worth a check.

Car looking good

John.

[mantasrme]

I'd check the ignition timing first, had one a while ago that ran smooth but was lack luster in performance.

Re-set the timing and was much better.

[Titson]

presumably you disconnected the ECU before you welded anything?

Maybe check the airflow meter is opening properly

[cam.in.head]

another thing that could take the emmisions very low is if theres a low fuel supply pressure.usually this would show up as a poor idle & more often than not poor power when you rev up not better as in your case .poss worth checking fuel filter is not partially blocked .or anything else such as pressure reg,leaking larger bore tank exit fuel pipe,crushed fuel pipes .?? worth a check. also check pipe betwween air flow meter & throttle is not split.

[Shuviteer]

Worn cam lobes.?

[85_GT/E]

Thanks guys for help so far sadly the Manta is not @ my house it lives at my grandads, our lass says im only allowed 1 Manta at our house!!! Bloody women good job she will never see this

I will check the air flow meter and pipe on Saturday, luckily i do have a few spares, the fuel lines are all ok i no that for a fact as i have replaced the majority of them all ready.

The car has been stud for the last 6 years on someones drive, i bought it and started to weld up all the holes then took for MOT so to be honest i didnt no about the fault with the car

its more of lack of power that a miss fire although i did here 1 or 2 pops through the exhaust poss unburnt fuel due to me having my foot on the floor boards trying to get away from the que of traffic im causing!!!!!

Yes i did disconnected the ECU b4 Welding if the wrong ECU is fitted could this cause this sort of fault????? just a thought as i did get a spare with the car but it is a different part number to the one fitted to the Manta???

[cam.in.head]

the wrong ecu would be useless. correct one is 0 280 000 301

also is the fuel feed the right way round.the haynes book shows it wrong. should be big pipe from tank to pump,pump to damper(if fitted!),damper to fuel filter,filter to t piece under injectors. the return back to tank from centre of pressure reg inbetween injectors.

[mantadoc]

the wrong ecu would be useless. correct one is 0 280 000 301

Actually the do run "OK" on the old 1.8 Astra GTE one! Not ideal but perfectly driveable.

[85_GT/E]

Hi just to update you on my Manta, i checked the ECU with the part number that (cam.in.head) gave me thanks mate, and found that the wrong one was fitted so i removed the one from my other GTE that i no worked, i also changed the air flow meter and added a K&N panel filter!!!!

Now all seems to be fine i just need to use her now for a while to iron out any other faults that may show there head, MANY THANKS GUYS , Paul

Just for interest the ECU that was on my car was 0280 000 304 and the little sticker is green any ideas what this ECU is for????? as i say it did start up and rev ok with this on it just had no power at all up to 3000rpm when engine under load

[Exclusive Opel]

Just for interest the ECU that was on my car was 0280 000 304 and the little sticker is green any ideas what this ECU is for????? as i say it did start up and rev ok with this on it just had no power at all up to 3000rpm when engine under load

Have a look here:

Link

[cam.in.head]

hopefully all should be ok now but i would go for the standard air filter. the air flow meter is calibrated with a paper element & to use a different one will make it weaker if it lets through more air !