Running problems with Lucas L (flapper 4CU) injection system

[esprits1v8]

I have just brought a TVR (wedge 350i)
It is not running very well, does not tickover (hunting and stalling)
does not rev very well did not like going over 2500rpm most of the time
sometimes would rev ok

has had an auto electrician test it and all sensors are working, diagnosed as faulty ecu plug or ecu
ecu plug has been cut off and spade ends fitted, was told this fixed the problem

however it has not fixed the problem, still the same!

I have now replaced the ecu plug wiring and changed the ecu (been told these were working) yes you guessed it no difference!!!

HELP!!!!

[softdash3.9]

If my auto electrician had done that to my harness I'd have cut his balls off I hope he's refunded any charges!

I'm sure Ramon will give you far better info than anyone else, hopefully he'll see this post

My Rover Vitesse has had a couple of spell of running rough, the first was one of the pins in the plug on the power resistor moved so was open circiut, so lost an injector or two.

The second time was the ecu, but you have changed it already.

Is it standars EFi as per vitesse or has things been changed?

Might be worth listing any changes away from standard

Is the ignition OK?, OE rotor arm/dissy cap, spurious ones can cause problems, as I found out mysely with my 3.9 RRC

[esprits1v8]

If my auto electrician had done that to my harness I'd have cut his balls off I hope he's refunded any charges!

no the owner cut the plug off and fitted the spade ends

"Is it standars EFi as per vitesse or has things been changed?"

yes as far as I know

" Is the ignition OK?, OE rotor arm/dissy cap, spurious ones can cause problems, as I found out mysely with my 3.9 RRC

will have to check but does look ok? too cold today to check!

[ChrisJC]

Download

http://www.cowdery.org.uk/downloads/Fla ... ual.tar.gz
It is 118Mbytes!

Work through the diagnosis (as a Land Rover technician would have done back in the day).

I have always found this process eliminates any fuel injection type issues.

But worth also checking for no air leaks or dodgy ignition system (maybe have a look under the bonnet after dark to check for tracking)

Chris.

[DaveEFI]

I have just brought a TVR (wedge 350i)
It is not running very well, does not tickover (hunting and stalling)
does not rev very well did not like going over 2500rpm most of the time
sometimes would rev ok

has had an auto electrician test it and all sensors are working, diagnosed as faulty ecu plug or ecu
ecu plug has been cut off and spade ends fitted, was told this fixed the problem

however it has not fixed the problem, still the same!

I have now replaced the ecu plug wiring and changed the ecu (been told these were working) yes you guessed it no difference!!!

HELP!!!!

There are lots of things which can go wrong, but before suspecting the worst, have you checked the basics? Ignition timing, plug leads dizzy cap rotor, etc? And examined all the inlet hoses for leaks? Does it start reasonably from cold? Also try unplugging the temperature sensor for the EFI on the nearside front of the inlet manifold next to the similar looking theremotime switch. That should make the mixture go very rich and stall it at idle.

BTW, your electrician is a w****r. But you know that.

[ramon alban]

It is not running very well, does not tickover (hunting and stalling) does not rev very well did not like going over 2500rpm most of the time sometimes would rev ok

Hello Jimbo, The primary causes (over 80%) of problems on the 3.5 Flapper 4CU Efi system is air leaks into the plenum plus connection issues around the Efi wiring loom, including the ECU connector. In that respect the AE was right to suggest the ECU connector as a cause, hopefully though, the previous butchering has not made matters worse.

A more recent cause of problems similar to what you describe is fuel tank contamination due to the ravages of time and modern fuel cleansing additives stripping stuff of the fuel tank innards, leading to crudded filters and pump.

Wherever you ask the question, such as here or (I see it also) on the tvr wedge pages, you will get loads of scattergun and anecdotal suggestions as to the cause, and if you are very lucky, one of them will hit the probem on the head, but sadly, youll probably win a tenner on the lottery before that happens.

Because you are using an AE, one assumes you may nott have the necessary diagnostic skills to tackle this yourself. Hopefully though you can handle simple instruments and carry out basic tasks when they are clearly laid out?

To that end I recommend the following 15 point health check designed specifically for the Rover SD1 Efi system pretty much the same as yours.

15 POINT HEALTH CHECK

Assuming the engine is in good mechanical condition with correct cam and lifter performance and timing, good compression within acceptable limits on all eight cylinders, good exhaust system with no leaks and fresh lubrication plus clean filters, then these 15 easy steps should seek out any health problems with the Rover SD1 Efi V8 system to improve performance from its current condition.

1 Clean all ignition components externally and internally, spray with moisture inhibitor such as WD40 and wipe dry. Ensure the distributor vacuum and mechanical advance mechanisms are lightly lubricated, working correctly and the springs/bob weights are free of any corrosion.

2 Check security and eliminate any corrosion on all ignition Low Tension connections right back to the ignition switch, including all local earth connections. Get some ideas here:

http://www.vintagemodelairplane.com/pag ... ing01.html

3 Clean and re-gap the spark plugs - replace if necessary.

4 Check for damaged or out of specification (measured suppression resistance) High Tension leads, Pay particular attention to the rubber boots. Clean and replace if necessary.

5 Set ignition timing to just eliminate pinking with normally available fuel. See here for a neat process.

http://www.vintagemodelairplane.com/pag ... ane01.html

(Note: Items 1-5 are to guarantee and maximise the best possible spark at exactly the right time. Check workshop manual for recommended component and timing specifications.)

6 Ensure the plenum idle air gallery is clear and not contaminated with goo.

7 Thoroughly clean the plenum breather gallery, flame trap and LH rocker cover breather filter

8 Ensure the throttle disc(s) is correctly seated at idle (or set to the recommended disc to tunnel gap where specified) to prevent "idle speed hang-up" and that the whole throttle mechanism is free of unwanted friction right through from accelerator pedal to throttle pot. (Note - items 6-8 are best performed by taking the Plenum Chamber to the workbench). Go here for Plenum Solutions.

http://www.vintagemodelairplane.com/pag ... num01.html

9 Set the AFM CO content to the recommended range erring just on the weak side of the mid-point. If a CO meter is not immediately available set the adjuster screw to 2.5 turns out, from fully home. See here for AFM stuff.

http://www.vintagemodelairplane.com/pag ... ter01.html

Reset idle speed to the recommended level. The settings are interactive so recheck both.

10 Set the Throttle Position Sensor residual voltage to 325mv (some spec's call for 350mv). Ensure the sensor is not electrically noisy, causing random overfuelling. See here for full detail.

http://www.vintagemodelairplane.com/pag ... Pot01.html

11 Verify the fuel pressure operates in the range 26 to 36 psi. not more, not less. Details here:

http://www.vintagemodelairplane.com/pag ... ply01.html

12 Test the integrity of the plenum and all its air/vacuum hoses for rogue air-leaks. How To here:

http://www.vintagemodelairplane.com/pag ... num01.html

13 Check all Efi loom wiring/connections for faults/corrosion including the Efi engine earth AND the engine earth strap. Unusual Efi Earthing Issues here:

http://www.vintagemodelairplane.com/pag ... ons01.html

14 Check and replace air and fuel filters if necessary. Ensure fuel tank is not generating crud.

15 Because the Plenum must be removed for proper cleaning and adjustment, lift and service the injectors, replacing filter baskets, pintle caps, fuel pipes and injector to manifold seals. See here:

http://www.vintagemodelairplane.com/pag ... tor01.html

If you persevered thus far, and are still reading you are also probably thinking "Oh Sh1t" and that might very well depend upon the depth of your pocket versus the extent of your workshop skills.

However, virtually all of the above program and the extensive list of links to downloadable and printable PDF's will ask you to depend only upon common sense, the use of basic tools, a multimeter and perhaps a fuel pressure gauge.

Another problem you will face is the one of "Basic Understanding" of the RV8 Efi Flapper System but please be assured - it is not rocket science - and with just a modicum of basic knowledge, the average owner/enthusiast can learn it given the right reading material in an owner/reader friendly format.

To that end you may wish to consider this:

http://www.vintagemodelairplane.com/pag ... ual01.html

Highly recommended, of course!

Sometimes when asking new owner/enthusiasts to deal with their issues as I recommend it sometimes overlooks the obvious original request as in the below quote.

It is not running very well, does not tickover (hunting and stalling)

Its just possible therefore that the following linked essay directly addresses your problem. I suspect not, because you also describe further non-related symptoms but you never know your luck! Have a read and see what you think?

http://www.vintagemodelairplane.com/pag ... ons01.html

[esprits1v8]

Thanks guys, yes have posted on a few sites and had a massive amount of help! no previous owner used the AE, I have fitted the correct plug back on the loom, and swapped the ECU (still no change)
I have complete flapper system to rob for parts, I plan to swap AFM next, and try it, then clean/check all hoses and connections, and work my way through all the parts a bit at a time..........will update later when checked more parts.

[softdash3.9]

Top Man Ramon

[DaveEFI]

Thanks guys, yes have posted on a few sites and had a massive amount of help! no previous owner used the AE, I have fitted the correct plug back on the loom, and swapped the ECU (still no change)
I have complete flapper system to rob for parts, I plan to swap AFM next, and try it, then clean/check all hoses and connections, and work my way through all the parts a bit at a time..........will update later when checked more parts.

The snag with using secondhand parts as a substitute check is you probably don't know the state of those.

It's perhaps natural enough to expect a major part has failed, but my quite extensive experience of this system says that's not so likely. What it can be is a build up of more simple faults over the years - and bodged attempts to sort things.

[esprits1v8]

checked all pipe work, no blocks or leaks, crankcase breather was blocked so cleaned it out, made no difference.
Checked the distributor cap and rotor arm, they are poor surprised they were not changed when HT leads got changed?
Tried the other used ones I got with the spare system, no difference.

Changed the AFM, Bingo did change it, the hunting on tickover has gone and revs a little better, took it for a drive, engine is still cold and is holding back like it has too much choke? will go for a drive latter and see how she goes! stuck baby sitting!
Thanks
Rob