37 replies to this topic

[gaffer1986]

My throttle cable is now spot on but my engine runs like a bag of bolts as low rpm's, sometimes tick over is lumpy, sometimes it's smooth, it sounds like it's going to stall when you give minimal gas before it revs up to 2-3000 rpm and today the eml flickered when I pressed the gas a tiny bit at tick over, it always smells of fuel and it occasionally back fires when coming off the gas suddenly at very low speeds. Does anyone think Northampton motor sport will be able to resolve any of these issues?

 

Also the red LED light in the engine bay is always on, Vocky said something about this being for diagnostics but I can't quite remember what?

 

It does drive superbly at 10%+ open throttle and uses surprisingly very little oil for a forged piston engine, but I do let it thoroughly warm up before I drive it very fast.

 

This is the engine spec:

 

[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]218.8bhp[/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]Saab Block[/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]Webcon ITB kit[/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]Alpha Pro 4 ECU[/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]Comp Cams Stage 2[/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]Double valve springs [/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]Forged pistons [/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]Steel con rods[/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]ZY crank shaft[/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]Balancer shaft delete[/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]Chris Tullet 4-1 manifold[/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]Chris Tullet 2.5 in complete exhaust[/font]
[font="'Roboto Slab', 'Times New Roman', serif;background-color:rgb(250,250,250);"]TTV light weight flywheel[/font]

 

[oakmere]

Out of interest do you need to set the throttle position sensor voltage with the TB kit? Just thinking it may have been altered whe fitting the cable.

[Arno]

ITB's usually are mapped using Alpha-N (absolute TPS position) indicating load, so indeed any work that touches/alters the TPS sensor, butterflies or their attached gubbins can quickly lead to odd running. Most obvious usually in the small throttle opening areas like idle and part-load running.

 

Probably needs a little TPS re-calibration after the cable and linkage adjustments to get to the TPS to the correct starting/zero point again so the mapping in the ECU matches again with the actual throttle openings.

 

Bye, Arno.

[gaffer1986]

Out of interest do you need to set the throttle position sensor voltage with the TB kit? Just thinking it may have been altered whe fitting the cable.

 

Nothing was altered when the cable was fitted, it ran like it before and after the cable was fitted. Fitting the cable solved the fact it was sticky and made the pedal travel smooth instead of clunky.

[gaffer1986]

ITB's usually are mapped using Alpha-N (absolute TPS position) indicating load, so indeed any work that touches/alters the TPS sensor, butterflies or their attached gubbins can quickly lead to odd running. Most obvious usually in the small throttle opening areas like idle and part-load running.

 

Probably needs a little TPS re-calibration after the cable and linkage adjustments to get to the TPS to the correct starting/zero point again so the mapping in the ECU matches again with the actual throttle openings.

 

Bye, Arno.

 

If this is the problem it certainly existed before the new throttle cable was fitted, fitting the cable was very straight forward and didn't change the butterfly position.

 

Could the TPS calibration cause it to back fire? How do you calibrate the TPS?

 

What really doesn't make sense to me is the fact the car feels like it is going to stall when you press the gas a tiny bit then suddenly revs itself up.

[fiveoclock]

Did you change the temp sendor like we discussed? You did say that you had odd temp readings on the gauge. If the temp sendor is duff you can get your problems. I had the same problems as you but my temp gauge read 999, changed the sendor and all was well. Try the cheap stuff first and a temp sendor is cheap

[gaffer1986]

I haven't yet, I have been thinking about it but my temp gauge doesn't do silly readings it just tends to stick to 82 which seems cool and can go up and down by 10 degrees. Also the fan came on the other day at just 87? Where can I get a temp sender from?

[vocky]

you have two temp sensders, the fan uses the one in the top hose and is set at 93 degrees. Therefore your stack dash has the wrong reading and so you need a new Webcon temp sender - which sits next to the thermostat like any other z22se engine.

 

Webcon would be the first place to try because it's specific to their Alpha ECU.

 

It has a blue coloured socket so is Webcon's - WTS104 Coolant Temperature Sensor - Vauxhall Type

[gaffer1986]

you have two temp sensders, the fan uses the one in the top hose and is set at 93 degrees. Therefore your stack dash has the wrong reading and so you need a new Webcon temp sender - which sits next to the thermostat like any other z22se engine.

 

Webcon would be the first place to try because it's specific to their Alpha ECU.

 

It has a blue coloured socket so is Webcon's - WTS104 Coolant Temperature Sensor - Vauxhall Type

 

Thanks Neil, I will try and get one.

 

Here is my issue, at 24 seconds I try to press the gas a tiny amount and this happens. Will a temp sender be likely to cause this fault?

 

[vocky]

your engine is still cold - no stack dash temp display, they are not at their best until the engine is warm.

 

I have to wait about ten seconds before even touching my throttle on mine.

 

I wish Alan was still about at Webcon, he can map cold starting and low rpm throttle settings perfectly. My last map he did was like a factory fresh car.

[gaffer1986]

It does this when it's warm also albeit not as bad.

 

Driving it at normal road speeds is a nightmare so I've got to sort it. I've bought a new sensor, was only £23 from Webcon.

 

I'm glad it is possible to make it good, why did your map not stay the way it was after Alan did it?

[vocky]

Alan mapped my 2.2 engine, which is now sat in your car, I now have a 2.5 engine with additional tweaks and had it mapped at NMS.

 

He spent a week mapping the 2.2 engine, NMS had only a morning. Therefore it was never going to be as good due to the time constraint.

[The Batman]

Thats what you get with a prehistoric ecu

[gaffer1986]

So you think it's all down to the mapping?

[Arno]

 

What really doesn't make sense to me is the fact the car feels like it is going to stall when you press the gas a tiny bit then suddenly revs itself up.

 

 

Not so odd.. If the TPS and butterfly relation or calibration is off the mixture will be a little off. Likely it's a little on the lean side.

 

As you just crack open the throttle the ECU is not 'seeing' much change with the TPS, but more air is getting into the engine. More are + same fuel == leaner still and that can make it misifre/stumble.

 

Once the opening gets bigger the differences/error in fueling tend to get smaller so it's not as obvious.

 

All in all it doesn't seem to me like a big problem, just that over time some bits have drifted/moved a bit and the car needs a little attention.

 

It's not uncommon on any ITB equipped car (or even cars with multiple carbs..) to need some periodic check/adjustment of the throttle butterflies and TPS sensors to make sure it's all in good nick. and alignment/calibration.

 

Depending on the style of ITB's and the linkages used it may even need periodic air-balance check on the intake to make sure all runners are sucking in the same amount of air.

 

Bye, Arno.

[gaffer1986]

That makes a lot of sense about air fuel. Thanks for you detailed response. Maybe I need a new TPS?

[gaffer1986]

Alan mapped my 2.2 engine, which is now sat in your car, I now have a 2.5 engine with additional tweaks and had it mapped at NMS.   He spent a week mapping the 2.2 engine, NMS had only a morning. Therefore it was never going to be as good due to the time constraint.

Does that mean your ECU is perfectly set up for my engine? I can buy your ECU please?

[siztenboots]

how about four carbs on there?

[vocky]

 

Alan mapped my 2.2 engine, which is now sat in your car, I now have a 2.5 engine with additional tweaks and had it mapped at NMS.   He spent a week mapping the 2.2 engine, NMS had only a morning. Therefore it was never going to be as good due to the time constraint.

Does that mean your ECU is perfectly set up for my engine? I can buy your ECU please?

 

 

the map was 241bhp and has been over written by the latest 270+ map, so pretty useless for you

 

Your car had a new TPS fitted a few years ago by Joey and the ECU has Fab's map on it (220-230 bhp)

 

I have the voltage written down somewhere for the TPS on Fab's map  

Edited by vocky, 29 July 2016 - 12:13 PM.

[vocky]

Unless someone has changed it the TPS should be set to 0.717v