My Simtek has developed a problem with the CEL light flickering about 5000rpm, in 4th and 5th gear. Its not the setting for the shift light because that is set at 7k so is it detecting DET or is it a software problem??

 

i would guess its detecting det..is it after being stationary and inlet temps have crept up??

 

I just been out in it and it seems intermittent. I can drive along at 80mph/4000rpm in 5th floor it and sometimes CEL light flickers yet i can go from a standing start 8k in every gear and its fine..

Ive always had a problem with the CEL light where sometimes if i start it the CEL comes on i then have to turn off the ignition and restart it and all is fine.

At this rate ill be removing it and fitting a different ECU!

 

Is it possible that it's actually doing what it's supposed to, and indicating that the engine is detting ?

Bad batch of fuel, over boost, or increased efficiency because of the colder weather ?

 

what Mark said..

Simon

 

But would it not do it all the time?? it really does seem intermittent. I would of thought it would do it whether im redlining it in every gear or just cruising along at 80mph but it doesnt.

 

no.. if the current tank of fuel is worse than mapped on, or colder weather has increased the boost slightly it will det depending on intake heat, load on the engine (road gradient), when the boost peaks (floor it at 3000rpm or 5000rpm) etc etc..

it flickering at 5000rpm in 4th and 5th at full throttle then avoid that for this tank of fuel.. or add octane booster..

Simon

 

What i meant to say in my second post was....If driving in 5th gear 80mph/4000rpm, if you start to accelerate the revs get to 4.5k and thats when it flickers yet ive driving hard in each gear and it doesnt do it.

 

there is more load in 5th gear, more boost etc..

Simon

 

Have you had the map 2 option set for lower octane fuel? If so try activating this map and see if the CEL warning disapppears.If it does then it is probably det and the ECU is doing what it should.
CEL light should come on when you first key on ignition.

 

And it does, but also it sometimes stays on until i turn the engine back off and restart then it goes out.

 

Couldnt that just be a dodgy knock sensor then ?




James

 

Sounds like your Simtek is doing exactly what it's meant to do.

If I motorway cruise then come to a stop and then accelerate hard the CEL will flash - it's simply the TMIC suffering heatsoak afaik.

I now add octane booster and this has resolved the det-issue.

Certainly don't get rid of your Simtek - cracking piece of kit imo (I'm very pleased indeed )

 

I had exactly the same thing after one of my Ecutek maps.

https://www.scoobynet.com/general-te...ml#post5178054

Floor the throttle from ~3-5k in 4/5th and I'd get a quick red flick on my KL. If I gave the car the full beans from lower revs through the gears nothing. Repeating it was a bit of a lottery, but when it did it the circumstances were always the same, high gear cruise- floor to WOT and flick.

It was the slightest of spits on the det cans and was easily sorted with a minor map tweak.

The reason it happened, in my case was I had some residual booster in the tank when originally mapped..

If it's det (and it sounds like it) putting in a good dose of booster (NF) should sort it..

 

Mine does it in negative boost, poodlin along minding my own business and then flicker flicker flicker. I was told it was due to the gear ratios and the ECU thinking you are going suddenly much faster than you are, prompting a very eager shift light ? I know others identical to mine that do it and I am not saying what I have been told is true. No det has ever been detected with the cans on all wired up to the laptop (again I am not saying what I have been told is true). All other suggestions would be superb, personally I would love to hear from other Simtek mappers/users, I only wish there was a resource bank to read of common easily fixable, diagnosable problems.

 

Probably not det in your case mate, maybe something setting off the knock sensors??

 

If the Gear ratio tables are not set correctly the ECU can be "confused" as to what gear is being used.This can cause a shift light problem...Also on early cars, the smoothing tables for the vehicle speed input signal need to be tuned to give accurate vehicle speed data.

The "resource bank" should be your original dealer or alternatively you can always call me on 07836 635001 and I will try to resolve any issues.

Steve s

 

It will be det, spurious dependant on conditions of boost, throttle, rpm ramp rate and others, if its flashing briefly and then stopping its mild, if its flashing and staying on then its something to be very wary of. Contact whomever mapped it and check at what sort of level he set the knock alarm table at, depending on that he can judge wether you need to go back or not. You could have a component starting to fail, for example the fuel pump could be getting tired, fuel pressure regulator failing, either or both would allow a leaner mixture, it could simply be that the ambient temps were much warmet when mapped and so now, being much colder hence denser air, you are a touch leaner.

bob

Simtek, Motec, Link, EcuTek, Bosch, DTA, PowerFC, ESL, Gems, Autronic
__________________________________________________ _____________

 

Any news on the Simtek knock control strategies?

Knock warning is one thing, but if users are either ignoring it, not trusting it or generally confused about what is happening then there stands a huge risk IMO.

The lack of an adaptive strategy on this seems to be a negative point in my eyes - you could never map it to the edge of what it is possible of.

 

Hi Steve, I will give you a call

 

IMO only a fool would continue to ignore a flashing cel light in any event, the op has immediately noticed his problem and posted asking for advice.
It sounds like it is doing its job to me and until it is established whether it is actually det or not, what is the point in trying to remove it with knock control.
A safeguard would be a nice idea though Duncan, and the guys are working hard on it along with all of the other upgrades people have requested.

 

The point is highlighted by the OP's thread in that he is questioning the software. Surely the doubt is proof in itself for the reason for a safeguard/safety net.

I can understand that most motorsport ecu's do not have knock control (although Motec have now introduced it as a free firmware upgrade) as these cars are heavily monitored. But, the majority of Simtek's are used in road cars and are replacing ecu's where knock control is an active feature - are these owners fully aware of the difference between knock control and warning?

As such I feel that first generation owners need a safety net to protect against fubarred engine's from a bad batch of (or wrong RON) fuel, overboost caused det or some mechanical/fuel issue causing det - it doesnt take long for an engine to grenade when experiencing det and maybe this would happen before they had time to question on scoobynet.

Second generation owners of these cars may not be so clued up and need even more protection.

Please don't take this as my criticising Simtek for the sake of it, once knock control is in there, I think it will be a cracking piece of kit But until then, I think mappers would have to err on the side of caution for a 'customer car' for fear of killing an engine.

 

Ah, I didn't realise Simtek lacked a Knock Control System, I'd back the CEL light up with a KS-3 or something similar.

 

Hello mate, are the simtek boards upgradable? If so would it be new hardware needed or just software?

 

The logic in going to a "warning" rather than a "control" strategy was that, unless you develop a fully adaptive ECU (as in the new age cars), you always are left with the problem of how and when do you reinstate the ignition timing that has been removed without then consistently repeating the det condition.Assuming that the car was mapped correctly originally, then you need to remove the root cause of the det before reinstating the timing.For this reason we felt that a warning system was safer, and even with a "control" system in place we would intend to retain the "warning" system.

You could argue that the early OEM ecu with a limited "control" strategy and no warning gives rise to the very problem I have outlined above.Det is detected and driver is unaware of det > ign reduced for a while > dets again > repeat until engine lets go! We stress to all our customers the significance of the CEL flashing; it is natural that this may be queried once it happens but that must be better than blissful ignorance.

I do take on board your comments Duncan and would only disagree in that I think the SimTek is already "cracking"; it will be "cracking plus" when the next upgrades are released!

Steve S

 

The reason i questioned it being a software problem is because of the other CEL light issue i have and also the fact that it seems intermittent.
When i first turn the ignition on the CEL light illuminates as supposed to but sometimes when i start the car it stays illuminated until i turn the ignition back off and restart the car so i thought the "flicker" problem might be an extension of this. Also on initial start up where the CEL stays on the REV counter doesnt work.

When i bought the car the guy told me that because of the Simtek ECU the ignition had to be left on for 20 seconds before starting which is what he was told when he had it fitted and mapped, to which i didnt question at first that was until i posted the "20 seconds waiting time" on this board asking other owners of Simtek do they do the same to which the answer was no.

As already mentioned in this thread i was just looking for advice and dont wish this thread to go off on a tangent about what the ECU can and can not do. Ive spoken to Steve via PM to which he is more than happy to look into my problems.

Jay

 

Do Simtek have a website, I'm not sure the ones I'm looking at are correct, they don't seem to mention the Subaru ECU. Ta.

 

What are the next lot of upgrades?

Banny

 

Smokingkills:

ECUs from #030 onwards are generally software upgrades.The knock control would be a software upgrade as the detection system is already in place.

Steve

 

if the rev counter is not working it will probably assuming you are in 5th (less rpm to speed signals for 5th) and the shift light is probably set to 0rpm (dissabled) in 5th and therefore it illuminates the cel light.. possibly an issue with the rev counter?

Simon