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View Full Version : Hitting rev limit @ 5k?



bodilx6
10-06-08, 09:15
When I floor it from a stand still or low speed, I seem to be hitting the rev limit quite a bit before my rev counter hits the redline.
Is this common? Why is it? Is the rev counter "to slow" to show the actual revs on the dial?

bolarbag
10-06-08, 09:17
Do you have a fcd and are you running stock boost?

bodilx6
10-06-08, 09:35
1st and 2nd decat, 3" exhaust, fcd, sld. So about as BPU as it gets :)
any thoughts?

Wez
10-06-08, 11:02
Sounds like it could be a fuel cut, what boost are you running?

I see no mention of UK spec or restrictor ring.

monkey3
10-06-08, 11:21
Mine does this as well.
Normally in 1st if you really give it beans.

I think it might be hitting the top limiter, but the needle just can't keep up.
I reckon you could find out if you managed to make it hit the limiter and then kept your foot planted to give the needle a chance to catch up... but I think I'll let you try that one first. :D

matt k
10-06-08, 11:23
Could it be overfuelling?

bodilx6
10-06-08, 11:35
No apparent overfuelling. I havent checked my wideband in 1st @ WOT though, but its normal and even maybe a tad on the lean side in higher gears.

*Could* be wheel spin, but then shouldn't rev counter still follow? (unless it really is slow)

Wez
10-06-08, 13:49
I have never seen a Supra rev counter not keep up, even in 550+hp singled motors.

Scott
10-06-08, 13:56
would pulling the timing cause this? Sounds like your ECU doesn't like something. Perhaps a faulty FCD?

Pig
10-06-08, 14:03
Have you got a boost gauge? What boost are you running?

Could it be that you massivly over boosting? Is there some kind of second cut. Or could it be the fact that your actually running out of fuel????

bolarbag
10-06-08, 14:12
Or could it be the fact that your actually running out of fuel????


I initially thought this, it cant be overfuelling thats for sure, faulty fcd or running out of fuel is what I'd say

Does the stock ecu compensate for lean conditions by introducing fuel cut - I dont think so, but it may do if your injector duty cycles are ludicrously high - which will be the result of overboosting

As wez mentioned you dont sound as if you have a UK car and no mention of a restrictor ring so this may be the case

Do you have a boost gauge?

Wez
10-06-08, 14:23
What boost are you running, some FCD raise the boost limit maybe you are hitting this.

Either way I suggest you stop booting it until you can figure out what it is ;)

colsoop
10-06-08, 14:46
You haven't changed your dials have you ?

DrifterWanaB
10-06-08, 15:03
iam still a bit wet behind the ears with the supra,

but are you running coil packs, if there breaking down it feels like a rev limiter, but usually it will pull through the misfire

Just a idea

Chris Wilson
10-06-08, 15:16
iam still a bit wet behind the ears with the supra,

but are you running coil packs, if there breaking down it feels like a rev limiter, but usually it will pull through the misfire

Just a idea

Sounds a likely cause, or plugs breaking down under load. When did it have new plugs? What are they?

bolarbag
10-06-08, 16:19
Sounds a likely cause, or plugs breaking down under load. When did it have new plugs? What are they?

I was just about to ask that - what are you actually feeling - fuel cut is head through the windscreen material
Rev limit is pretty much a noise and a slight loss in power, spirralling the more you hit it

Is it consistant this rev limit and have you got more than a quarter of fuel in the car?

Do you have the stock ecu and only the stock ecu?

monkey3
10-06-08, 17:07
Maybe mine's not like this...
For starters mine only happens in first and is joined by a big braaaaapp and it only happens if the wheels are spinning.
I'm sure it's the limiter, but it's very difficult to look at the rev counter and the road at the same time.

Scott
10-06-08, 17:09
Maybe mine's not like this...
For starters mine only happens in first and is joined by a big braaaaapp and it only happens if the wheels are spinning.
I'm sure it's the limiter, but it's very difficult to look at the rev counter and the road at the same time.

Don't floor it when your doing it, let the engine rev up slowly to the limit, not slowly so that you have it at 5k revs for 10 seconds or anything, just so that you can keep an eye on it and the road.

Daston
10-06-08, 17:16
mine will sometimes happily hit the limiter in first however other times espesially on hot days it will loose momentom at around 5.5-6k

wilkorangerover
10-06-08, 18:38
i had this trouble but in third it was throttle position sensors

wewsupra
10-06-08, 21:18
i got this problem in 2nd its doing this a 5k
i got no cats and fuel defender but no boost controller lol

Ric
10-06-08, 21:22
Misfire from incorrect temp ranged plugs

5k rpm is about the range where you will be hitting full boost 1.2 should be, standard plugs will not like that

bodilx6
11-06-08, 13:36
Have you got a boost gauge? What boost are you running?

Could it be that you massivly over boosting? Is there some kind of second cut. Or could it be the fact that your actually running out of fuel????

Running around normal BPU boost. 0,8 or so in 1st as max i think.
No massive overboost at least

Wideband is also around normal, as mentioned. Only a bit lean in high gears. 13 or so in 1st i would say


iam still a bit wet behind the ears with the supra,

but are you running coil packs, if there breaking down it feels like a rev limiter, but usually it will pull through the misfire


Sounds a likely cause, or plugs breaking down under load. When did it have new plugs? What are they?


Everything about the coils are stock. Actually just puchased new coils plugs since the old ones are getting a bit brittle.

I have the platinum toyota plugs, gapped to 0,7mm. should be ok. When I first got these plugs it definately misfired since they were gapped like standard plugs. It didn't misfire untill 2nd or 3rd gear anyway. And its definately not the same here. If it should be the plugs, wouldnt it also happen in 2nd and higher?
It only happens in 1st and not the same "cut" if you can say so. Misfire is more of a, yeah, fireing sound repeated much faster than this

My car was 100% stock J-Spec before i got teh 3" exhaust, 2nd decat and kept the 1st cat with a hole punched through to add the resistance of a restrictor ring.

bodilx6
11-06-08, 13:38
I was just about to ask that - what are you actually feeling - fuel cut is head through the windscreen material
Rev limit is pretty much a noise and a slight loss in power, spirralling the more you hit it

Is it consistant this rev limit and have you got more than a quarter of fuel in the car?

Do you have the stock ecu and only the stock ecu?

Not like fuel cut. Had that one before I got the FCD. More like you describe the rev limit. Should be with more that a quater of fuel, but I'll check as soon as I refill.

Stock ecu and only that one.