On occasion and it happens at least once in a (even if only driving five minutes) span whether cold or warm....

RPMS will rise and drop, whether it's at idle, part throttle, etc. Sometimes it'll drop down to 0 then up again to 4000, then down again while driving...ERRR!!

Swapped in a NEW ECT & 2 bar MAP - no effect

It has a L1 ECU w/ Stage 1 chip....(bought the car like this)

Car was rebuilt from shell using a cut-up harness that was resoldered.

Checked plug and it seems OK, a bit dark but not sooted on the first plug so i left them alone....

It doesnt help that the nearest Cossie place is over 1000 miles away I couldnt trust to drive the car more than a mile anywhere since it's dangerous!

Any suggestions??

 

ok i know fook all about these engines but not long after i got my cossie
the rev counter did exactly the same thing, bouncing all over the place,
i called the AA out (recovery firm) he did a few tests on various things and told
me the ignition module had packed up, black thing on inner wing as i knew it

he put a new one on and its been fine ever since.

got to be worth a look mate, good luck

 

sounds good - but i already replaced that!

but i bought a used one - maybe i should buy a new one & check again.

 

maybe,
he also recommended i changed the coil as quite often when the module goes, the coil follows not long after.

hope ya get it sorted mate

 

cheers mate - just ordered a NEW igntion module and waiting for me mum-in-law to arrive from N'castle with a whole load of Cossie goodies i had sent to her including a used coil known to be good.

RSCAT - THANK YOU - YOUR A REAL MATE

 

when you say the revs roll about, is the actual engine doin this, or just the tach?

If just the tach.. check all the LT side of the ignition, especially Ign Amp, amp plug and the capacitors on the coil (Remove them)

 

the engine - as it will buck while driving!!

 

btt

 

what i dont follow is hos the engine can go from 0-4000 rpm whilst driving...

It simply cant mate....

Have i missunderstood you?

 

No it can!! It will do that!! Quite scary...

Thanks to technology i have a couple of 1MB mpegs demonstrating the problem:

Pls only download if trying to help, as there are download bandwidth restrictions:

http://www.geocities.com/merouby/bucking1.MPG
http://www.geocities.com/merouby/bucking2.MPG

In bucking1 you see it happening in the beginning but normal driving torwards the end.

In bucking2 it happens towards the end.

Cheers.

 

Looks to me like just the rev counter is moving, not the engine speed...

Example.. if you were in 4th gear whilst this was happeneing, are you suggesting the car is accelerating on its own, from 20 - 90pmh and back to 20 again in 1 second?

 

no it was BUCKING - tried my best to keep the camera steady - the car would accel- stop-accel-stop - never make it above 50mph

 

Im baffled then im afraid..

If your confident the engine definately accelerated itself to 4K rpm IN GEAR, then back down to virtually stall.....

I can understand some faults causing the rev counter to do just that.. but not the engine too...

What sort of road speed and gear are we talking about here?

 

yes, it would go to 4k for only a half a second then drop so it's not like it's a speeding train, but at times, it does squeel tires while this is happening - happens at any gear, at any speed

 

Does it do it with the throttle closed? If the engine rpm is rising, could you have an air leak into the system past the throttles? Like a loose inlet manifold for example? On my first ever car, I changed the downpipes and you had to take the inlet manifold off as well. In my haste to get home, I forgot to tighten the manifold bolts up and when I started the engine, the revs were all over the place, up, down , almost redlining. Just a thought.

 

Ok..
Given the engine IS accelerating, as fast guy says, we have an air influx.

First of all, remove the ISCV plug and see if it helps.

If it does, you have most likely got a faulty TPS.

 

any joy with this yet mate? sounds a real odd one, when my module went it
affected the running, but just a little, kind of hesitating a bit as the rev counter
went up and down.

 

No, have disconnected the ISCV with no effect - but i was reading in an old issue of Fast Ford that Well Lane in West Yorks reckons it's either an overcharging alternator or a dirty TDC pickup. Will clean, check/change plugs, rotor/cap and possibly even change pulse sensor at this point. Also will gap plugs closer for US fuel. Have a NEW module to try out as well and a spare STOCK L1 ECU. As a result, I have a huge set of spares for it now!!

Just came back from a visit to NY and now I got a few car errarnds to fix: Mazda 323 that needs a master cylinder and a Chevrolet van that needs a coolant leak fix, so it may take me a while to get back to you guys on this. But cheers for the help, like.

 

tried spare L1 ECU - no effect...will keep you guys posted

 

changed spark plugs/rotor/dizzy cap - everything worked PERFECTLY until i turned it off, then when restarted, it went back to it's old stalling ways

 

PROBLEM SOLVED - It was the bloody dump valve. Blocked it off, and it ran fine. Now it reaches 9 psi (which it never did before - max 6). So it was a vacumn leak then and now I got a whole bunch of spares

 

NOPE - HAPPENED AGAIN!! Dammit!!

 

Well the vacumn leak from the dump valve was real and made her run bad, but i think i sussed out the above problem: today I replaced the coil with a used one I bought, and now the problem seems to have disappeared. Mind, i've only been testing it for an hour, like. (Like me Geordie accent? )

 

Nope, problem happened again! ARGGG!!! Shall I convert the car to carbs and ditch the turbo??

 

Go back to the XR4TI, the cossie is too much of a man's car for you

 

Fuck u Fastmaul, mate! I fixed it! FINALLY! It was the feckin phase module in the distributor. Changed it myself - did all the work myself - I am my own freakin mechanic!

The old one had it's wiriing taped up in the distributor!!! Cheap ass b'turds who put in my engine!!

When u get ur Cossie and if u need help, i'll be happy to give u a hand!

Was loving it on the hiway doing 100 mph with my English mum-in-law, wife and kids lovin every minute of it - man does my car have BALLS!!

 

Glad you fixed it fella. I thought mine was fixed but it died on me this morning again. But if it turn everything off and reset the alarm it starts and drives off again.

Will have the alarm replaced this weekend and hope that sorts it otherwise I'll be replacing all the bits you have

Paul.

 

cheers mate - wish u sort that alarm out and it ends ur woes - wouldn't want u to suffer like i did!!