7A hesitation/flat spot

[goodall]

This has got even worse now, cant pull out of junctions, onto a motorway or even just cruise at certain speeds without her bucking or dying out.

I have an aan and a pt (3.6 v8) sitting here and thinking either be a nice swap but would really love get the 7a to run

[SA BOY]

Bloody frustrating, I had a similar problem with a standard sedan 7A and eventually gave up and scrapped the car. Would not rev past 4000 in gear, swapped out everything but no joy. Thinking back now it must of been a problem with the loom?

[goodall]

Been starting to think is it a broken wire somewhere and its exactly the same 4000rpm and dead

[SA BOY]

Yeah check all your earths first then maybe open up the loom.

[zefsider]

I've heard no mention of your injectors yet...are you still using the stock Hitachis ? These are by now well past their sell by date for sure...and in any case are better replaced with LS1/Bosch conversion . Maybe this is your problem ? My stuttery idle and rough acceleration was transformed after I did it...cheap mod if you source carefully...ask me how


Don't give up, theres not enough 7A's left !

[goodall]

Last night I blanked of the crankcase breather to make sure not getting unmetered air but problem still there

I have bosch injectors but issue still occurs with them and a spare set hitachis, went to audi today see if any there mechanics might experiance with the 7A but no luck was told be at least £200 just have looked at...

[zefsider]

maybe an intermittent short between injector ( any one of them ) and the ECU
Maybe also your bypass wiring on the resistor pack .
You said weak spark....have you changed leads/checked for integrity of leads ?
last thing I can think of is change the fuel pump relay ( ? number 215 ) ( or maybe the pump is on its way out....you have tested it but not to say it is again an intermittent fault , noticeable at high revs but not lower down ....I think I have similar prob at the moment but only when starting ....the pump can have good and bad days until total fail...if its whining or making similar noise it could be ready to go , expensive to replace though just on the off chance , unless you have a spare...

good luck , damn these 7A's, but I still spend more on mine than on my girlfriend... ( cos she's worth it )

[trebormc]

Hi mate, have you check the fuel pump for full flow and system pressure? I had a 90 quattro sport which wouldn't rev past 4000 and that was fuel starvation at or near full throttle.

[goodall]

I have a new pump on the car but its very noisy and do think it may be a possible suspect more and more but seemed to flow ok. Thinking about by passing the relay with some wires direct as changed the rely but still suspect a fault is possible

The leads have been replaced with set good silicone ones.

I'm thinking checking the cam timing at the weekend just on the off shot its out causing engine run outside of the map

[trebormc]

Are you running the 2 plug ecu? And what is the rev counter doing when the car starts to hold back?
Does the counter drop to zero?

[sidrick]

Only just read this from start to finish and would be very interested to hear about the problem when it is found. Sounds fuel related to me. Does the 7A run an accumulator after the pump?

[zefsider]

I reckon deffo fuel ....pump, or relay...or how about a blocked fuel filter ...noisy pump equals 'on the way out' ( or not fitted properly in the tank, is it in-tank on the 90? )

No accumulator on the 7A/EFI....only on CIS/K-Jetronic i think...The 7A has FPR , cos the pump runs constant pressure ...the FPR regulates the pressure as requried.....checked that FPR too BTW ? There is a way to test the thing by bypassing the fuel relay, you need a gauge on the rail , should be between 3.8 at about 2k revs, up to 4.2 Bar at WOT ...only know the theory, never done it

I really want to know the outcome of this too , fingers crossed mate

[goodall]

So today I had push start the car twice, is possible does anyone think that a bad battery could be the cause of this? I replaced the alternator few weeks ago

Yea two plug ecu, rev counter keeps reporting the engine rpm when the misses happen

New filter on the car but I have an other new one I might try on, possibly worth getting a gauge and a whip to check fuel pressure. Another think I would like check is if keep getting a spark when happens so might try using the strobe light to see

[zefsider]

No start after cranking ? Quick, pull out a plug, see if its wet with fuel, if not....

[goodall]

Nope, just wont crank, replaced the battery starts perfect but fault is still there

I have a 4 plug ecu and loom, all i need is the bracket for the pot as have it too and strongly thinking swapping the loom over see will make her run proper