SUCCESS!! Car is running perfectly - shunting gone !!
Discussion
I am sure it is not often you come across a thread where someone does not have a problem so I thought I would share my joy in finally getting this car to run with hardly any shunting.
Thing is, it is running on the original 14 CUX and not on an aftermarket set up and also it is still on the stock map ('white' tune), ie ECU is working with the narrow band lambdas and not the 'green' tune where they are ignored. There is no new ECU or 3D mapping or any other custom mapping of the 14CUX on this car right now.
So what did I do?
1. Checked all the wiring in the engine bay, and rewired the earths, rewired starter cables fitted an Odyssey battery in the boot. Wiring for all this was as fat as my little finger (can't remember the cross section size). Now seeing nearly 14 volts on the voltmeter in the dash.
2. Replaced HT leads and coil with new Bosch items - ie standard leads. Carefully routed these with spacers from the dizzy around the engine to ensure no crossovers
3.Changed sparks to NGK BPR6ES - got rid of extenders - checked gaps to 0.8mm and carefully fitted these and tightened them. Made sure all leads were nice and tight on the plugs. HT leads protected with fibre/rubber cable protector sleeves and then titanium boot protectors over the lot. HT leads held tight to rocker cover to keep them away from the exhaust manifolds.
4. Removed the injectors and had them cleaned. Was told that even though I had run a couple of bottles of injector cleaner through in the last 6 months, that they were in a sorry state. Refitted, them, new O rings and checked fuel regulator pressure - all fine.
5. Checked TDC mark with piston stop method, reset all the HT wiring around the dizzy (they were in order but set on the wrong number 1 cylinder), then opened up the dizzy, lightly greased the weight pivots, and set the timing at 28 deg at 4k. Rotor arm and dizzy cap from Powersparks.
6. took crankcase ventilation apart, cleaned wired mesh and mushroom hole, replaced the foam in mushroom and replaced all hoses with jubilee clips.
7. replaced vacuum pipe and rubber angled hose and left it on the ported vacuum point.
8. Removed stepper housing from the plenum, completely cleaned it out, replaced hose from stepper motor to plenum. Dismantled stepper motor and cleaned it. Set base idle to 600 rpm.
The car also had these mods by the previous owner but not sure of their contribution.
ACT Y-piece (but I also removed pre-cats)
silicone intake hose
carbon trumpets and red silicone heat shield under trumpets
My car has covered 118k miles and is running like clockwork now, and hardly any shunting at the 1500 - 1800 rpm area and it can trundle along in 5th at 30 mph without playing with the clutch. It goes over speed bumps in second without my needing to feather the clutch.
So far the first 100 miles have been smooth, the car feels quieter, no fuel smells coming into the car and the gear shift feels light and slick. There is no hesitation in the throttle response, both around town, and opening it up on slip roads, it really is a pleasure to drive, even in traffic and the temp gauge has stayed steady around the fan on off mark in traffic. At WOT power feels strong and there is no feeling of the car running out of breath over 4k rpm.
It has often been talked about that these cars must have behaved well when new and this has shown that if everything is working properly as far as ignition and fuelling is concerned that there is still something to say for the old 14 CUX and clockwork dizzy.
I know it can be improved upon if I was going to be very fussy with this, idle is still lumpy at 950 rpm even though it is idling with around 14 deg advance (only have 14 deg of mechanical advance from 28 deg at 4k rpm), although I would suggest this is to do with the HC cam.
I will try it on the green tune to see if there is an improvement on this, but part of me is tempted to leave it as is.
Thing is, it is running on the original 14 CUX and not on an aftermarket set up and also it is still on the stock map ('white' tune), ie ECU is working with the narrow band lambdas and not the 'green' tune where they are ignored. There is no new ECU or 3D mapping or any other custom mapping of the 14CUX on this car right now.
So what did I do?
1. Checked all the wiring in the engine bay, and rewired the earths, rewired starter cables fitted an Odyssey battery in the boot. Wiring for all this was as fat as my little finger (can't remember the cross section size). Now seeing nearly 14 volts on the voltmeter in the dash.
2. Replaced HT leads and coil with new Bosch items - ie standard leads. Carefully routed these with spacers from the dizzy around the engine to ensure no crossovers
3.Changed sparks to NGK BPR6ES - got rid of extenders - checked gaps to 0.8mm and carefully fitted these and tightened them. Made sure all leads were nice and tight on the plugs. HT leads protected with fibre/rubber cable protector sleeves and then titanium boot protectors over the lot. HT leads held tight to rocker cover to keep them away from the exhaust manifolds.
4. Removed the injectors and had them cleaned. Was told that even though I had run a couple of bottles of injector cleaner through in the last 6 months, that they were in a sorry state. Refitted, them, new O rings and checked fuel regulator pressure - all fine.
5. Checked TDC mark with piston stop method, reset all the HT wiring around the dizzy (they were in order but set on the wrong number 1 cylinder), then opened up the dizzy, lightly greased the weight pivots, and set the timing at 28 deg at 4k. Rotor arm and dizzy cap from Powersparks.
6. took crankcase ventilation apart, cleaned wired mesh and mushroom hole, replaced the foam in mushroom and replaced all hoses with jubilee clips.
7. replaced vacuum pipe and rubber angled hose and left it on the ported vacuum point.
8. Removed stepper housing from the plenum, completely cleaned it out, replaced hose from stepper motor to plenum. Dismantled stepper motor and cleaned it. Set base idle to 600 rpm.
The car also had these mods by the previous owner but not sure of their contribution.
ACT Y-piece (but I also removed pre-cats)
silicone intake hose
carbon trumpets and red silicone heat shield under trumpets
My car has covered 118k miles and is running like clockwork now, and hardly any shunting at the 1500 - 1800 rpm area and it can trundle along in 5th at 30 mph without playing with the clutch. It goes over speed bumps in second without my needing to feather the clutch.
So far the first 100 miles have been smooth, the car feels quieter, no fuel smells coming into the car and the gear shift feels light and slick. There is no hesitation in the throttle response, both around town, and opening it up on slip roads, it really is a pleasure to drive, even in traffic and the temp gauge has stayed steady around the fan on off mark in traffic. At WOT power feels strong and there is no feeling of the car running out of breath over 4k rpm.
It has often been talked about that these cars must have behaved well when new and this has shown that if everything is working properly as far as ignition and fuelling is concerned that there is still something to say for the old 14 CUX and clockwork dizzy.
I know it can be improved upon if I was going to be very fussy with this, idle is still lumpy at 950 rpm even though it is idling with around 14 deg advance (only have 14 deg of mechanical advance from 28 deg at 4k rpm), although I would suggest this is to do with the HC cam.
I will try it on the green tune to see if there is an improvement on this, but part of me is tempted to leave it as is.
Classic Chim said:
Does that say 118,000 miles Steve and yes congratulations are in order. Your perseverance has paid off.
I notice the cars the right colour too. Just lovely mate.
That's right, 118k and tight as a drum. I notice the cars the right colour too. Just lovely mate.
A well used car was one of the criterias I had before I bought it as I can use it all year round here quite easily and did not want to be afraid of putting on the miles. It is a triggers broom though as now most of the components have either been upgraded or replaced in the last 5 years.
I would recommend this route to ownership rather than a low mile car that has not had much use as it is also the best way to learn all about your car.
Steve
I’m so pleased for you that your hard work over the winter has paid off and you’ve proved there is still life in the humble old 14CUX. You have a real beauty in one of the best climates in the world and hopefully your economy is better.
I’m so pleased for you that your hard work over the winter has paid off and you’ve proved there is still life in the humble old 14CUX. You have a real beauty in one of the best climates in the world and hopefully your economy is better.
jazzdude said:
idle is still lumpy at 950 rpm even though it is idling with around 14 deg advance (only have 14 deg of mechanical advance from 28 deg at 4k rpm), although I would suggest this is to do with the HC cam.
Sounds like your less machine advance is a blessing in disguise as it allows you to run more advance at idle.ChimpOnGas said:
Great result, nice job 
If you now run a full manifold vacuum signal to the vac advance to give 18 degrees at idle, then run the engine a little richer at idle and just off idle..... you'll move it forward by further noticeable amount.
Cheers, Dave.
Thanks If you now run a full manifold vacuum signal to the vac advance to give 18 degrees at idle, then run the engine a little richer at idle and just off idle..... you'll move it forward by further noticeable amount.
Cheers, Dave.
I'd like to try that Dave but I don't have enough mechanical advance on this dizzy to start at 8 - 10 deg at idle.
Im going to be look for a used dizzy with 20 deg mechanical advance and then would love to try it.
Edited by jazzdude on Saturday 7th April 23:07
stevesprint said:
Steve
I’m so pleased for you that your hard work over the winter has paid off and you’ve proved there is still life in the humble old 14CUX. You have a real beauty in one of the best climates in the world and hopefully your economy is better.
Cheers Steve, and thanks too for all your help and encouragement. I’m so pleased for you that your hard work over the winter has paid off and you’ve proved there is still life in the humble old 14CUX. You have a real beauty in one of the best climates in the world and hopefully your economy is better.
At this point which of the maps you have would you recommend I try on green tune while keeping the same white tune (2967_400.bin) I have to fall back on?
jazzdude said:
Cheers Steve, and thanks too for all your help and encouragement.
At this point which of the maps you have would you recommend I try on green tune while keeping the same white tune (2967_400.bin) I have to fall back on?
SteveAt this point which of the maps you have would you recommend I try on green tune while keeping the same white tune (2967_400.bin) I have to fall back on?
I think you’ve got the best idea getting your engine running as best as possible on the standard chip, then let me know if you want your lingering coasting (open loop) idle lowered or your you stationary (closed loop) idle changed.
R2967_400 contains the standard Griff 400 PreCat and the early Chimmy 400 CAT maps merged together so you can switch between CAT and non CAT without changing the chip. If you run the non cat map don't for forget to set your CO Trim screw, Clockwise is more volts and more fuel, I set mine 4.3L to 1.4 volts which is just over the mid point in RoverGauge but I don't know if that suits a 4.0.
If you have RoverGauge please can you tell me your Checksum fixer on the top right of the screen for you factory chip as it would help to know if you have the early or later Chimmaera 400 map as your 1995 is near the change over point.
TVR made the following small changes between 1994 and 1997, which some I don’t fully understand
| Chip Offset | Parameter Description | Early (1994) | Late (1997) |
| 137 | Fuel Cut On Hi rpm | 0A=2,500rpm | 10=1600rpm |
| 14B/C | Fuel Cut Decel reinstatement | 00 C8 | 00 64 |
| 14D/E | Fuel Cut Decel after speed drop | 00 F0 | 00 8C |
| 175 | Stepper Dead Band (not adj if less than) | 02 | 01 |
| 176/7 | Base idle Speed Stationary (Closed loop) | 03 52=850rpm | 03 20=800rpm |
| 159/A | Idle increase Park/Drive/Manual | 00 64=100rpm | 00 64=100rpm |
| 1F4/5 | Subtracted from Throttle POT | 00 37 | 00 23 |
| 1F8 | Temperature force open loop | 7A=30° | 99=17°c |
| 7BB/C | Map 5 Rpm Limit | 05 0D=5800rpm | 04 B0=6250rpm |
| 7BD | Map 5 Warm up threshold | 6A=38°c | 6E=36°c |
| 7BE | Map 5 Warm up threshold | 27=83°c | 2C=78°c |
| 3FEB | Checksum Fixer to 01 | 9B | 5D |
Fuel Cut on overrun
The three fuel cut parameters will cut the fuel when you back off above 1,600rpm or 2,500rpm, 1,600rpm is best for fuel economy but 2,500rpm might induce a few overrun pops.
Stepper Dead Band
The later setting of 01 is the standard Land Rover 3.9 setting and allow for more fine adjustment of the stepper than the earlier 02 setting which is the same as Chimmy 450s and Griff 500. Maybe I'll experiment with this in the summer to see if it makes a difference.
Base Idle and Idle Increase
I’ve included ‘Idle increase Park/Drive/Manual’ as its added to “Base idle Speed when Stationary”, you can see TVR reduced the later idle speed from 850+100rpm down to 800+100rpm in the later version.
Subtracted from Throttle POT
Unknown use
Temperature force open loop
Stops lambda control below 30°c or 17°c
Map 5 Rpm Limiter
RPM Limiter changed from 5,800 to 6,250rpm
Map 5 Warm up Thresholds
Unknown use, the earlier settings are the same for Chimmy 450s and Griff 500s, where as the later thresholds are from early 3.9 Land Rovers.
Checksum Fixer to 01
The checksum fixer should always be recalculated after changing any tune parameters so the whole tune file’s checksum adds up to 01. Hacking the fuel table without recalculating the checksum fixer will trigger fault code 29 – ECU Checksum Error.
It would be interesting to see of you could spot any difference between the early and later Chimmy CAT maps other than the idle speed and RPM limiter, then you could let me know if you want the best bits from each chip.
Only a thought.
Steve
Even though some of the items in the list had been done before (leads, coil, dizzy cap and rotor and amp) and I still had the 'hesitation' you say or shunting at around the 1700 rpm mark.
The above items were replaced again this year (just to set a new datum point) and I suspect that the difference probably is to do with the cleaning of the injectors and setting up the timing and vacuum.
The above items were replaced again this year (just to set a new datum point) and I suspect that the difference probably is to do with the cleaning of the injectors and setting up the timing and vacuum.
I had a similar experience. Mine was a bit hesitant when I got it so I replaced all the ignition components that looked a bit tired and had an old school krypton tune test done / run on the rolling road - identified suppressors fitted to the nearly new distributor cap that were promptly thrown in the bin, suggested the cats might be a bit blocked (possibly from not being booted enough!!! chucked a bottle of cataclean through it) but otherwise the engine in good health.
It’s been running really well since. I’ve just fitted the ACT induction hose and noticed a sharper pick up.
Now it looks like we’ve seen the last of the snow and having got a fresh mot yesterday (no advisories 😁) I’m going to try Steve’s updated files - i’ll report back on how I get on.
It’s been running really well since. I’ve just fitted the ACT induction hose and noticed a sharper pick up.
Now it looks like we’ve seen the last of the snow and having got a fresh mot yesterday (no advisories 😁) I’m going to try Steve’s updated files - i’ll report back on how I get on.
I had a similar experience. Mine was a bit hesitant when I got it so I replaced all the ignition components that looked a bit tired and had an old school krypton tune test done / run on the rolling road - identified suppressors fitted to the nearly new distributor cap that were promptly thrown in the bin, suggested the cats might be a bit blocked (possibly from not being booted enough!!! chucked a bottle of cataclean through it) but otherwise the engine in good health.
It’s been running really well since. I’ve just fitted the ACT induction hose and noticed a sharper pick up.
Now it looks like we’ve seen the last of the snow and having got a fresh mot yesterday (no advisories 😁) I’m going to try Steve’s updated files - i’ll report back on how I get on.
It’s been running really well since. I’ve just fitted the ACT induction hose and noticed a sharper pick up.
Now it looks like we’ve seen the last of the snow and having got a fresh mot yesterday (no advisories 😁) I’m going to try Steve’s updated files - i’ll report back on how I get on.
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