my99 wagon's

as title really uk my99 turbo hit's a wall of some sort at 5k rpm.

whats the most common fault that could cause this?

thanks in advance

Splitpin

You've not really given us a lot to go on. Would help to know whether the car is standard or modified - especially in the induction tract area, and what the exact nature of this "wall" is. Do you hit it only if you accelerate hard, or does it also happen under light throttle? Is it always at exactly the same engine speed, or does it vary a bit? If you have a boost gauge fitted, what sort of pressures are you seeing when this happens? Has it started happening all of a sudden over the last couple of days, or has it gradually been getting worse for a while? Have you seen the Check Engine light come on while the engine has been running (and have you checked for stored error codes just in case you missed it)?

Answers to those questions will help us help you. If you look in my posting history you will also find some information that will help you work out the age of your mass airflow sensor, and help you decide whether replacing it might be a worthwhile diagnostic step.

my99 wagon's

ok m8

powertec induction
3" decat straight through to rear silencer
td04
fmic

never checked what happens to the boost! dah!! althought it pulls strong to 5k.

hard or light throttle it still happens at same revs as if it don't want to pass that point

i've only had this one for a couple of weeks its done it since i got it and never had time to investigate

engine check light doesn't show or anything and it does work i checked that today also i don't no how to check the ecu code's on this

i have another my 99 wagon that runs perfect

Splitpin

Ah. Has the ECU been mapped for the induction kit and front mount intercooler? If not, while there are many other potential explanations, it is eminently possible that the "wall" is being caused by a mass airflow sensor misread either caused directly by the presence of the indiction kit, or caused indirectly by it as a result of accumulating sensor damage - or a combination of both.

Either way, if the modifications haven't been mapped in, the best thing you can do is remove them and replace with standard components. If you have another (standard) car of the same model year, you could swap the relevant parts over and see if that solves, or at least influences the problem.

Search will tell you how to check for stored error codes (search for "black plugs", inc the speech marks). And, as above, establishing the age of the MAF sensor would be a good move, although there isn't much value in replacing it if you're going to keep the aftermarket induction stuff on.

my99 wagon's

thanks splitpin i'll have a play tomorrow see what happens i don't no if its been mapped as i've just got it as a toy for a bit.

prob not been mapped though and was thinkin of going simtec anyways

my99 wagon's

UPDATE:

had a little play today. done ecu code check come up with afm. so i reset the ecu done a run and found that the boost gauge goes to 0 bar boost on 5k rpm

what would cause the boost to just go to zero?

i,ve done a check of all the connectors and t-clamps there all secure no obviuos problems, vacuum side was a bit dodgy to the actuator but sorted that out before another run!!!!

my99 wagon's

changed the maf today still no good

Jolly Green Monster

iTrader: (4)

Inlet pipe sucking shut?

Jolly Green Monster

iTrader: (4)

In fact if its the air filterwith the corrigated pipe to the inner wing it is way to restrictive

my99 wagon's

really? an i was going to pull the dump valve off tommorow for a run think its a cheapy!

so if i pull the air filter off for a trial that'll tell me

it is that type filter

Jolly Green Monster

iTrader: (4)

Good call, it could also be dump valve

I would try not to run with no filter, refit standard airbox?

my99 wagon's

a little hint would also be that it don't happen at 3/4 throttle suggesting its maybe suckin the hose in also

don't have standard airbox well a do but its on the wife wagon

Jolly Green Monster

iTrader: (4)

Swap it for a test