Low Power ?

[Avonvilla]

I'm starting to pull my hair out now, please help......

Ok car is an S2 with precat still in but a 2.25" from there back with no main cat. Has a k&n and a bailey recirc dump valve. Last week i fitted an everest chip and all seemed fine if not quite as great as i was expecting. I sent Alan my logs and he confirmed my suspicions that i was well down on power, he reckons as much as 50bhp ! Since then i've put in new plugs, redone the timing which was out by about 4 or 5 degrees and today messed about with the dump valve, i disconnected the vacuum line to stop it dumping but still low power ? I know the precat may be restricting optimal bhp but i'm getting about 150 tops with an everest ! thats down on stock really dont what to do next although selling is feeling good ! Please please help................

[Costas]

If your Precat or Cat is destroyed or messed up, it could prevent your engine from "breathing" properly.

[Avonvilla]

Thanks for the quick reply, so even thou i am hitting .9 boost a clogged precat could result in low bhp ?

[Candles]

Brakes binding
Crappy fuel
Valve timing
Exhaust restriction

[Avonvilla]

On inspection of some old logs it would seem i have been down for quite a while, in that time i've had new brakes etc so not that. Loads of differant fuels have been in all normal unleaded, would that really give a 50bhp loss ? What do you mean by valve timing ? The precat is beginning to look like the next culprit to check

[ESM]

Steve,

Sorry I haven't got round to your latest logs yet

You data indicates CTS and MAT were 2-3°C different at ambient temperature. This isn't wildly out but it may indicate a calibration issue that gives bigger errors as the temperature increases. When the engine is at temperature where is the engine temperature raedout on the dash pointing? If the temperature is nominal (low-mid 80s) then it should be pointing at around 1/4. If this is the case I would think about the CTS. See here for more diagnostic stuff. You could take it off and check the calibration using boiling water or something. The MAT is easier to check. Its calibration is also in the engine management manual.

[Avonvilla]

It's ok Alan you must ged fed up with all of us !

Normal engine temp is about 1/4 and then goes upto just short of 3/4 when the fan kicks in, i had the thermostat changed last service as the heater isn't wasn't getting that hot, dont know if that points to anything ?

[Avonvilla]

Alan, can you send me those "good" S2 logs so i can do some comparrisons please, my email is steve@maceweb.com

Thanks

[ESM]

When I get home....

[Avonvilla]

Thanks Alan will be most appreciated.

I did a complete cold on the driveway to fans kicking in today and the coolant seems to run high ? Started at around 27.5 and rose to around 86 when there is a dip to 82 where i presume the thermostat opens, then it rises again up to 111 before the fan kicks in and drops to 102 then the cycle repeats. From the graph i saw of Alans on one of the posts this seems very high ? If so what could it be ? On the same run the MAt started at 29.5 and rose steady to 72.4 when the test stopped.

[delta]

..........so even thou i am hitting .9 boost a clogged precat could result in low bhp ?

Ofcourse it can. You have 0,9bar in a wide band of rev's with the everestchip, eventhough the airflow through the engine is doble as high at 7000rpm, compared with 3500rpm.

Intake and exhaust airflow are direct connected and I think that what you see is the restricted exh. just allowing enough flow to spin the turbo to deliver the 0,9 bar, and even though the revs are higher still just allowing a max. airflow as you have it at 4500rpm, where the engine power output is -50 of max power.

If you have used leaded fuel your precat it is almost 100% garantied your problem. The cat is build up of hundreds of thin tubes with a special active coating inside. Leaded fuel coat the inside of these tubes with lead, prevending the cat to work, and at the end blocking all the pipes off. So you are ending up with an engine loosing power for every mile you drive.

As damaged cat`s can not be repaired, my advise is to emty the precat for its contens of material, and you will see the full benefit of the Everestchip.

[Avonvilla]

After hours of trawling the service books and pdf's i think the cooling is fine on all counts so the precat is the no1 candidate i think, luckily davidjt donated his old SE one which i was going to use for testing differances so i'll just bolt that on and see what happens.

[Candles]

Don't you mean; "We'll struggle with all the bolts, shear them off coz they're seized in and then get really angry with it, then just bolt on the spare pre-cat...."

[Neil D.]

try reading this

http://www.lotuselancentral.com/forum/v ... php?t=1310

Neil

[Avonvilla]

Don't you mean; "We'll struggle with all the bolts, shear them off coz they're seized in and then get really angry with it, then just bolt on the spare pre-cat...."

I'm not doing it

[Avonvilla]

try reading this

http://www.lotuselancentral.com/forum/v ... php?t=1310

Neil

Errr changed the plugs already ?

[Avonvilla]

Right just had the empty precat fitted and drove home, didn't feel like i found 40bhp but i'll log it anyway

Exhaust gut suggested air/fuel ? or leaky hoses ?

[Avonvilla]

No change

Can someone confirm that with the everest say at about 2.5k rpm you floor it and the boost gauge jumps to about .4 then there is a "lag" till it then rises to .9 at a slower rate ?

Help guys i'm gonna hit the bottle soon

[delta]

Can someone confirm that with the everest say at about 2.5k rpm you floor it and the boost gauge jumps to about .4 then there is a "lag" till it then rises to .9 at a slower rate ?

Don't that suggest that the wastegate is stuck in an half open possision.

[Fubar1764]

Smell the exhaust when you're running. No, not in leiu of the bottle! Might you be running a bad mixture? Too rich or too lean perhaps? Clogged fuel injectors?
Are you losing 50hp at the motor or at the wheels?