Struggling at high rpm
 

Hi all,

My bug eye has the following mods. Straight through system, green cotton filter sti intercooler, walbro fuel pump and a Forrest remap which runs on 0.9 and 1.3 bar.

In either map I notice that the car struggles from around 5k onward, it almost chokes up and stumbles but will go to the top if pushed. Any ideas?

It's otherwise good up to 5k

Cheers

mine the same, seems to pull fine up to 5.5k mine an sti tho, but i have come out of a high reving N/A so this is my 1st turbo so maby im expecting more aha

sounds like overboost

Care to elaborate? :)

Doesnt sound like overboost at all IMO.

Sounds like one of the following :

1 - blocked uppipe cat (replace with an sti decat uppipe)

2 - you have fitted a set of aftermarket ebay headers and they are rubbish ...

3 - The TGV system is locked closed on one or either side of the engine ... this is less likely but does happen


My money is on 1

btw 6 volt it will be causing damage if you try and push it up there through the stumble until you change the offending part.

Thanks for the advice, the headers are standard, and the system is completely catless ( larger free flowing up pipe ) the engine has recently been put back together after the last block died ( how I bought it ) so now has the 2001 heads on a 98' block. The last one looked as if it has been run lean and melted a piston. I have had afr ratios checked and all seemed well but would choke up at around 5 k...could you explain this tgv system please

What year is the car ?

Did you fix the problem that caused the last engine to die or just replace the engine ?

Could be fuel pump dead, injectors blocked, fuel filter blocked ....

the tgv's could well be giving you sh*t but would also give you a light, ive had problems with them on my 03 wrx when my icv gasket went it gave me the codes for the tgvs and when i replaced the gasket the light and codes went away. tbh the symptoms are similar:wonder:

^ assumes that CEL light hasn't been removed from the dash. Seen lots like this unfortunately.

Hi,

I am not getting any cel lights.

We have not fixed the issue that caused the last block to die, just thought that it had let go, but obviously there is another issue.

I will check the fuel filter... how do i test the fuel pump? it must be working at the lower end of the rev range, but how can i test it under a high load situation?

Easiest option would be to whizz it onto the dyno at DSA and see what the fueling is doing through the rev range... or get an experienced mapper to check it over. I'd be happy to do it for you as often passing aylesbury :thumb:

I had it checked at edm Motorsport near Bicester before I knew it had the 1.3 bar map, so it was tested for the afr ratios etc on that map. The dude said that the fuelling was very good and had no concerns but the power dropped off drastically at the 5k mark.... Which only netted me 185 hp... But I did find a big split in the intake pipe also.

I'm going to stick some 99 Ron in it to see if the type of fuel is an issue. / knocking back the timing ?.. Been using 97/95...as its a uk car but I'm guessing it's been mapped for 99

Ps . How much would you want to have a mooch ?