intermitant lurching

[ukhozi]

I know I have posted this before but so much has gone on it's a whole new think tank needed.
Car is a 1995 1.4 sport C14SE engine. so no complicated ECU, no CAT, just the basic 8 valve stuff.
In an attemp to cure it I have replaced; Ignition modual. plug leads, plugs, throttle position sensor, idle control valve and crank position sensor. so in other words all the ignition and sensor system. I have check for loose connectors and brokern wires, new air filter.
When driving 'normaly' it lurches, sometimes quite violently unless I de-clutch, rev up and slip in the clutch (which is not slipping or grabing), kinda 'kangaroos' like a learner driver. If I 'floor' the gas it goes like a scalded cat through the gears and revs cleanly up to and beyond the red line but try driving at normal pace and in comes the lurching, yunk, yunk, yunk. But here's the strange bit, it's not all the time. I can drive 15 km and it's a pig, visit a shop and then on the way home, sweet as a nut!
Any ideas, anyone had the same problem and CURED it?
Help please, the wife is so on my case.

[Jason_Corsa_B]

Did you reset the ICV settings when your replaced it ? Put ignition on and disconnect battery, leave for half hour or so then connect back up (NEGATIVE TERMINAL & while ignition is still on) then start the engine and don't rev it for a few minutes.... try this a few times and see if it helps. Also what about the air mass sensor ?

[ukhozi]

Air mass sensor on a C14SE? there is an air flow sensor which I have replaced, basicly I have replaced everything under the bonnet.

[ukhozi]

ECU 16163449 QX BFZN
NO engine managment lights or codes on this model.

All connectioins on the ECU are clean, looks like new.

Lurching getting a bit worse but when it goes away all is 100% !!???

[octane41]

sounds like the idle control valve is only working intermitently

[ukhozi]

Did you reset the ICV settings when your replaced it ? Put ignition on and disconnect battery, leave for half hour or so then connect back up (NEGATIVE TERMINAL & while ignition is still on) then start the engine and don't rev it for a few minutes.... try this a few times and see if it helps. Also what about the air mass sensor ?

Trying it as speak, (type) but does this work with the early pre-99 ECUs (as shown above post) or only on the 'chipped' ECUs?

[ukhozi]

OK tried that three times no change, Reved the nuts of it in neutral which cleared something for a while.
This engine (C14SE) has NO EGR valve, Diagnostics socket, Engine managment light, no paper clip option.

[ukhozi]

Not to speak too soon but reving the nuts off of it seems to have shifted something. We did 100 miles yeasterday down to Gibraltar and back and sweet as a nut, trip into town for Burger King last night and still OK, If the missus comes home from another trip to Gib' with the thumbs up it could be sorted, buggered if I know what it was though, but I know what it wasn't.

[ukhozi]

Still running sweet as a nut
Found the socket to the left of the fuses.
Thanks all, here's hoping it stays good.
Peter

[ukhozi]

Didn't stay good, managed to do the paper clip test and first time got the normal code 12 x3 followed by 93 followed by 22.
Disconnected battery for 10 minuets and codes went away and took it for a 10 mile test run and it went possibly best ever. No light came on so wife took it to work 70 mile round trip and on came the light again, test showed code 22 again but 93 had gone this time.
Unwrapped the loom from bulkhead to injectors and check all the wires and connectors, loose bound and fitted new ribbed tubing and taped up leads to sensors, still showing code 22. Removed TPS all OK and refitted it, still code 22 anyone know what the tech’ talk "Low voltage" actually means and what to look at?
While doing the teat the ICV was ratteling which I don't think it did before!!

[ukhozi]

Took the ECU out and undid all the plugs next to it, found the larger of the two a bit 'green' and cleaned it nothing elase wrong I copuld se, dropped the glove box and checked there, all seemed OK too. still does it. adjuted the static tickover screw and found the engine managment light would go out if I increased to stop,(increased voltage to TPS?) gave it a run and it seemed OK. wifey off to work in it today so see what happens.
Anyone, HALLO ANYONE, know if this code 21 & 22 is relative to the throttle stop screw?
Peter

[4992jk1]

TPS low voltage means one of two things, either the tps output to the ecu is shorting to ground somewhere, or the 5v feed to it is damaged somewhere and isn't getting to the tps, if you pull the plug off and get a multimeter across the negative battery terminal and each pin in turn one should measure 5v with the ignition on (position 2)

[ukhozi]

Thanks, I'll stab the begger with my multimeter first oppertunity. I checked all the wires and re covered them from the ECU to the injectors so I'm sure it's not a short. I though it might have been relative to the throttle stop screw because as I screwed it up (increase tickover) the light went out, went the other way and it came on again??

[ukhozi]

It has been surgested that it might be the Lambda sensor on the exhaust header, what say you. one on order anyway as they are only £25

[ukhozi]

OK changed the Lambda sensor, no change, changed the throttle position sensor, (again) no change,
re-checked all the wires from ECU to engine components and re-covered with new corrigated tubing. no change
I have ordered a new puel pump on the of chance it could be that but I very much doubt it.

Yumpty, yump yump, here we go again.

So far in total I have replaced;
Crank sensor
Idle control valve
Throttle position sensor (2)
Air flow sensor
Air filter
Oxygen sensor
Ignition modual
HT leads and caps (OEM)
Plugs
Fuel filter
Wireing covers
Striped and cleaned ECU contacts and opened up for a corrosion check, OK
Cleaned all multi plug connectors
Nuffin' left under the bonnet, confused???