Throttle Bodies / TPS on R500 Duratec... Cause of lumpiness?

[Guest]

So having some lumpiness from my R500... After every 500 (or so) miles, it starts to be more lumpy and can stall when pulling up to traffic lights, junctions etc, unless you keep blipping the throttle that is. Whilst the throttle blips sound good, it does get a little irritating...

 

...Heard somewhere the throttle bodies or the throttle position sensor is the cause. Is this something that can be fixed, or is it something I'll have to keep getting adjusted...??

 

 

 

Edited by - Roadracer1977 on 13 Aug 2014 20:36:00

[ChrisC]

Really can't comment on the R500, but my Sigma 150 is on throttle bodies, and if they are not balanced and the TPS is not perfectly with the correct idle speed, it starts to become a pig to drive. Including stalling etc.

[nickh7]

Daniel what ECU is it? I had a Scoobie Diesel that did the same thing and I was told it was the ECU resetting itself. It took two swaps of ECU before it settled down

[Guest]

Quoting nickh7: 

Daniel what ECU is it? I had a Scoobie Diesel that did the same thing and I was told it was the ECU resetting itself. It took two swaps of ECU before it settled down

I'll take a look tonight and report back. I seem to think it's something to do more with the throttle position sensor, and like ChrisC suggest balancing the throttle bodies.

[paul abrahams]

Try sitting in the car at various throttle settings (whilst stationary) and get some kind person (swmbo) to very gently wiggle the TPS and wiring to see if there is any variation in revs.

Worked in diagnosing my faulty TPS 6 years ago and been fine since

[MartinH]

There is lots of discussion round this kind of thing in the archives. I have a similar set up (though an upgraded R300D not an R500) and adjustments to bring things back into line do need to be made from time to time.

 

There could be other things to check but at least make sure of the following:

1. At idle, the roller barrels are set to 6mm opening. A 6mm drill bit shank is a good thing to use to check this.

 

2. TPS at idle set to 4.62 Volts

 

3. Each of the 4 trumpets should be drawing in air at the same rate and if not the barrels can be adjusted/balanced. You'll need a synchrometer for this.

 

Mine was set up a few months back and had started to be 'lumpy' as well. Did all the servicing tasks a few weeks ago including the above and its fine again now.

 

Cheers,

 

Martin

[geko]

Hi,

 

I think you have this TPS fitted to your R500 roller barrel:

http://www.caterhamparts.co.uk/product.php?id_product=4056

 

If you can read the TPS voltage in your MBE ECU it is no big deal to adjust it again.

Mostly the TPS have to much play an read 0% while you have already open the throttel a bit and the engine will stall to due lean AFR.

 

Here you can read (start at page 28) how to fit this TPS:

 

CSR260 Cosworth engine build manual

 

 

Edited by - geko on 15 Aug 2014 08:31:23