Misfire/lumpy accelleration

Jon Kent · Post by **Jon Kent** » Thu Nov 30, 2006 6:20 pm

Okay, firstly, I'm new to the really old stuff, so expect some dumb questions.
The 2.4E (Esmerelda) has lovely stable tickover, will tootle along smoothly in traffic, but when you try and slowly accelerate, she's really lumpy. If I floor it, she picks up fast and smooth.
E had major engine work (though not actually rebuilt) in 2000, but has only done about 6000-7000 miles since (over a thousand with me) and had hardly run in the 12 months before I bought her.
Any ideas ?
Thanks in advance,
Jon

Nick Moss · Post by **Nick Moss** » Thu Nov 30, 2006 6:39 pm

I would get the throttle linkages checked to make sure that the butterflies all open at the same time. if not you would get uneven running at low throttle openings but the problem probably wouldn't be felt at bigger openings.

Jon Kent · Post by **Jon Kent** » Thu Nov 30, 2006 7:05 pm

Thanks Nick.
As I'm currently Jonny foreigner (literally!) I'll be looking myself, as I don't trust anyone near here with the old stuff.
Does anyone have any recommendations for books, workshop manuals, etc. I'm quite handy, just lack experience on the pre 1990 stuff, as I've spent the last four years playing with 964s.....and still do.
Though give me the rattles, the smell and the lumpy pickup anyday

Will take it through the Luxembourg MOT on Monday.....that should be a challenge. Managed to get it on historic plates so it's number is 72023.
I'll post pics soon.
I'm rambling.......
ENJOY,
Jon

Alan @ CanfordClassics · Thu Nov 30, 2006 9:47 pm

Hi Jon,

Nick is right check all the basics first, amongst others, check timing, gaps and so on. But if I had to edge a guess I suspect the MFI may need adjusting. I did one for a friend a few weeks ago which ran poor (ish) at idle, but none the less worked ok, ok at full acceleration, but lumpy in between. In this case the reason was it was running far, far to rich at idle. It really needed a rolling road for the best/fine tune but we had it driving like a different car within a few hours.

HTH

Alan

Gary71 · Post by **Gary71** » Thu Nov 30, 2006 10:09 pm

Mr Moss

I've been struggling with my car recently, it's been getting harder and harder to drive smoothly, idles OK and fine when wide open. Just been taking another look tonight and I find the RH ball joint on the cross linkage has come loose so the banks are totally out of synch at anything other than idle (springs holding the butterflies on the stops) and wide open (you holding them against stops with your foot).

Nice one

Jon Kent · Post by **Jon Kent** » Fri Dec 01, 2006 8:12 am

Many thanks Gents,

I've allocated some time this weekend away from the kids, to be anti-social in the garage. Though I have set out some old blue 911 seats at the side of the garage, in case anyone wants to come and speak to me.

I'll let you know how I get on.
It'll be a shame to fix, as I quite like flooring it, 'because I have to'......officer.

Enjoy,

Jon

Gary71 · Post by **Gary71** » Fri Dec 01, 2006 8:19 am

I quite like flooring it, 'because I have to'......officer

Seems a shame not to gun it sideways out of every junction

The car is much improved this morning, although I'm still on 5 cylinders, worked fine on my old Audi Quattro

Glenn75S · Post by **Glenn75S** » Wed Dec 13, 2006 9:35 pm

When you say lumpy running is it at a certain rev range in a certain gear. Although I have CIS, its still MFI and I know when the injectors are past their best you can suffer in the mid range ie 30-40mph at 2500-3500rpm in 3rd, ie the engine runs pretty lean, when you floor it more fuel is added and the car picks up quickly. Check when your injectors were last changed.

Not sure if it is the same problem with early MFI as CIS but there is a recommendation not to drive the car under load in a high gear (it basically kills the injectors via backfires...