okay have a look at this video guys
basically when my car warms up (85°C+ oil temp). sometimes the revs drops to 0, but car will still run. when the revs drops to 0, the revs seems higher than it was before it dropped (i can hear its a bit louder).
this only happens when oil temp is 85°C or more.

only was to fix this is by turning off the ignition, and restarting the car. but after a small drive it will happen again

im running simtek ECU. (Mafless setup)
ive changed the idle control valve, and even had a swap for another throttle body from a friend
anyone had this issue before, and know a fix
might be the ECU needs mapping



wiley

 

also ive noticed that on my boost controller, that when the revs drops, the injectors displays 0% too (normally 50%)
again, when i restart my car its okay again. revs seems normal and the injectors go back to normal too

could this be coil pack/spark plugs, or injectors maybe? but how would this make my revs drop to 0

wiley

 

does it stall when you come to junctions etc? i had the same problem although running standard ecu, the throttle settings was reset and idle was tuned this cured the problem

 

it does sometimes, but cos its revving by itself, it doesnt as much...

 

yip mines was the same would bounce from 0 to 1200 then back a few times, it may not be the same issue i had but it was really annoyin, speak to your mapper get it reset and take it from there

 

think needs a map, but this is strange...

Wiley

 

...

 

Does the engine actually sound as though its about to cut out or does it run as normal but the rev counter drops to 0?

 

doesnt cut out, it sounds like you're revving the car a bit. i can even drive without touching the throttle when it happens . bit like cruise control.

Wiley

 

You may have an air leak, check all the vacuum and intake hoses, you could also spray brake spray, easy start round the hoses to see if it changes the revs, if it does then you'll know where to start looking.

If this dont work id probably try the coolant sensor next

 

ill check out the vacuums probably at the uxbridge show. will have the car warm up on the way down there. coolant sensor?

wiley

 

Invest in a data logger IAM might be jumping about

 

still not resolved, any ideas guys?
basically when the car does this (the 0 revs), its the same noise/sound as when i unplug the idle valve

any help appreciated, im from rm13 if any guys local can give me a hand

wiley

 

Just out of curiosity, who mapped it? Have you been in touch with the mapper for this problem?

 

Hi Wiley

I would suggest speak with yours mapper first,maybe is something what can be easily sorted

But as above guys suggest Coolant sensor can cause this,Coolant sensor is located in crossover pipe,Here is the picture where is it



But first I would speak with yours mapper,if not speak with Neil@Slowboy racing,I'm sure he will able to help you,he is not far from you


Jura

 

That looks like a pig to change!!!!

 

It's not as bad as it seems tbh, just remove alternator to get access and be sure you have the new coolant sensor to hand to swap straight away as that way you avoid a airlock in the coolant system

 

Oh ok. Still looks messy tho lol. .

 

Cheers guy
quick question, why would the coolant sensor effect the revs?

wiley

 

...

 

AFAIK the ECU looks at the coolant sensor and works out what the idle should be......... keeps the idle high when cold and drops it when warm.

Faulty coolant sensor can mess around with the idle but usually within what the ECU sets. Aftermarket ECU's tend to have a poorer cold start regimen than OEM so cold idle sometime a bit rough.

Sounds like it's a mapping issue plus a dodgy sensor (temp / throttle position) somewhere.

Shaun

 

thanks shaun, i doubt its the coolant sensor, but for £10 a can get a replacement and check.
i thinks its to do with dodgy sensor or wiring somewhere. possibly an ECU issue, but i'll let that be the last on list.

wiley