Technical Turbo hesitation?

[craig20vturbo]

Hi,

I bought my Coupe 20v Turbo at the weekend, it's totally standard and has full Fiat servicing. I'm shocked at the pure acceleration on this thing! especially 2nd gear. It's put a huge grin oin my face since I first got in it, what a great car! My last car was A Lancia Delta Integrale evo 1 and I'd say it feels as quick as that but obviously no competition in the handling dept.

Anyway..

The only problem I'm having is when I put my foot flat on the floor in 3/4/or5th gear it seems to accelerate really hard from 2k up to 3k rpm then it'll hesitate slightly and then another wave of intense acceleration will take it up to 4.5K and then it'll hesitate slightly again before pulling hard up to 6k.

The car was sat on the drive and not used for just over a month, but since I got it on Sunday I've done 150 miles and the problem is the same.

Is there a way I can diagnose what's causing this, could it be to do with the overboost? The car is still extreamly fast but I feel there's something holding it back ever so slightly.

Any advice would be very welcome

Thanks
Craig

 

[MrB]

Possibly the EBV needs cleaning (pierburg solenoid), it's the brass coloured thing in front of the battery tray. Run some carb cleaner or the like through it.

(soory for the hasty reply, bit busy just now with a classroom full of folk, I'll try and be more help later if I can. Pretty sure someone will have given you more detail by then)

 

[craig20vturbo]

Hi MrB,

Thanks for the promt reply. I've taken the solinoid off and given the two contacts a clean, doesnt seem to have done anything tho. What exactly does this solinoid do anyway? Is it for the overboost?

Might take her to a garage some time this weeke and hook up to a fault diagnostic machine and see if it's anything obvious.

Cheers

 

[MrB]

You need to take the pipes off and clean through the valve. If you apply 12V to it it will activate, do that a few times while spraying carb cleaner in the holes.

Or, if you have a boost guage, just replace it with a 15 quid PBV. You need to set this to a safe boost limit though, 1.1 - 1.2 bar is the max for fuelling on a standard car.

Just looking for a site that explains the pierburg EBV nicely, watch this space (I would have directed you to FCCUK, but the forum went down taking all the useful info with it!!)

 

[hmallett]

If you are in need of a PRV, I have one spare, which can be yours for £10 (including delivery). Note that you need a boost gauge to monitor the boost levels.
H

 

[craig20vturbo]

Thanks for the pointer guys.

Thia is all new to me so I have many questions.

How exacltly do I apply 12v and to what to clean the pipes from the EBV?

what's a PBV or a PRV?

My car doesnt have a boost guage and I'm not sure how to connect one, how do I set the boost limit?

 

[Scooby-FCCUK]

I have a how-to on cleaning the EBV, have a look here: http://homepage.ntlworld.com/paul-baker/cleanEBV.htm

You can also apply 9v using a PP9 battery, should be enough to open the valve without the risk of electrocuting yourself

 

[craig20vturbo]

Hey thanks Scooby. I'll try that on Saturday and let you know how I get on.

Cheers
Craig

 

[craig20vturbo]

Cleaned the EBV today and now it's accelerating nice and smooth all the way :slayer:

Thanks for your tips

Might just be me but it does seem to be boosting slightly less now, maybe it feels like that as it was surging before.

Cheers
Craig

 

[pinin__prestatyn]

A PRV should sort that out, and makes the car feel a lot faster, as boost is instantaneous. Can be a bit snappy in the wet though, before you are used to it.

 

[h2ypr]

Good to see it was something simple!!!

Pinin.... i have yet to fit my prv.... whats it like in real terms?

Ross

 

[pinin__prestatyn]

Aha Ross, always a pleasure

The car feels much faster with the PRV, no doubt about it. There's no hesitation or any of the smoothness you get with the PRV, just savage boost that arrives immediately. However, you have to be careful with the way you drive when using a PRV, especially in wet.
The sudden snap of torque to the front wheels means you can spin 'em very easily in the first 3 gears, and if you floor it when cornering sometimes you will just understeer straight into the corner if you don't correct it ! it's because you get full boost with your foot only half way down the accelerator.
It sounds worse than it is, and once you revise your driving style you don't notice it.
Best thing is fit it and find out for yourself

 

[hmallett]

I think you meant to put EBV in place of PRV at some point there Matt.
H

 

[h2ypr]

But u can still drive on low boost tho? like with motorway driving etc? or just poodling in the town?

Ross

 

[hmallett]

What you really want is an Electronic Boost Controller. That way you can set the boost level easily to whatever you like, so run base boost (0.8 bar) round town, moderate boost (1.1 bar say) during spirited driving, and high boost (1.2-1.3 bar say) for that "must pummel Imprezza driver into the ground" moment.
Cost is about £250-300.
H

 

[h2ypr]

Yeh H i know i need one. But a PRV is only £20 and i dont have the money for a boost controller the now. I have just spent £2000 modding my coupe. Gt28r, Evo 6 FMIC and 3" exhaust etc all adds up!!

Ross

 

[pinin__prestatyn]

Hiya H yes I said "none of the smoothness you get with the PRV" when I meant to say EBV but I hope you "dig me" anyway
I want an EBC, they are great for having a low boost for traction and good MPG, and a high boost setting for when that skyline is threatening to make a meal of you!
I guess the only reason you would go for a PRV is you can pick them up for £20 and they do the trick. A cheaper EBC option would be a switchable PRV from Cosmo, so you could have base boost, then with a flick of a switch back to say 1.2 bar. Only costs about £70 too.

 

[turbo16vmark]

Has anybody got any links for these parts?

 

[craig20vturbo]

The

 

[hmallett]

Eh?