850 t5 boost problem!!!!!!!!!!!!

[s2esc]

Hi everyone im a new member and am new to t5's aswell (just got mine yesterday). My problem is that my t5 drives fine when taking your time but when you put your foot down it stutters a bit in low gears (1\2\3) but its not to bad. but when you get up to about 80 ish and your in 4th or 5th gear and you floor it it stutters hard untill you get to about 4000 rpm ish then it pulls like hell again. any help would be much appreciated thanx.

[fraz13]

Hi :welcome:

Do you have the lambda light on??

Could be a vacuum leak, check the small rubber elbow between the power steering resevoir and attatched to the inlet manifold

[Andrew]

Welcome to the site - I'm sure you'll find answers to all or at least most of your questions here :)

Ac.

[Mrsmopp]

Sounds either like a boost leak or the ECU retarding. Do you have an 850? if so how far into the white does the needle go on the boost gauge when you floor it?

x

[Babybadger]

Hi everyone im a new member and am new to t5's aswell (just got mine yesterday). My problem is that my t5 drives fine when taking your time but when you put your foot down it stutters a bit in low gears (1\2\3) but its not to bad. but when you get up to about 80 ish and your in 4th or 5th gear and you floor it it stutters hard untill you get to about 4000 rpm ish then it pulls like hell again. any help would be much appreciated thanx.

I had the same thing at about 80ish and found the mechanic (and they should no better as they work with T5's regularly in the south east .....no names) had not replaced the air inlet pipe properly next to the radiator, it is a kind of venturi funnel that connects to the piping that goes to the airbox and MAF,worth a check!

[s2esc]

firstly thanx everyone. yes it is an 850 L,reg the boost needle goes all the way to the end of the white. the lambda light is not on but does light up when the ign is turned on (so the bulb is still there). i also thought that it was maybe a boost leak cos i had a simular problem whith an old rs turbo. when i get chance in the week ill try changing spark plugs n checkin all the boost pipes and vac pipes ect. ill let you know what happens. Cheers.

[Mrsmopp]

I dont suppose its a burgandy Saloon that you are talking about?

The needle for a stock T5 shouldn't go all the to the end of the white - have you had any modifications done?

If it has a bleed valve or MBC on it may well be overboosting and thus retarding.

x

[T5Rdragon]

Hi everyone im a new member and am new to t5's aswell (just got mine yesterday). My problem is that my t5 drives fine when taking your time but when you put your foot down it stutters a bit in low gears (1\2\3) but its not to bad. but when you get up to about 80 ish and your in 4th or 5th gear and you floor it it stutters hard untill you get to about 4000 rpm ish then it pulls like hell again. any help would be much appreciated thanx.
Hi and Welcome. I have a very very similar thing on my V40 T4 recently. The fix was really simple and unexpected for the symptoms; I replaced the spark plugs and the car was like new again.

So, if they haven't been changed recently, I'd try a new set of plugs first.

[fireclown]

sounds like plugs to me too m8. welcome to the forum

[s2esc]

It is burgandy but its an estate there are no mod's that i know of, everything looks prety stock to me. i have jus been having a quick look at it and found that
the cold air intake pipe to the right of the rad was not connected to the air box properly so ive pushed it back on (should it be jubilie cliped on). i'v not had chance to test it yet though im also definately going to change the plugs on mon. ill let you know how it goes. Cheers.

[nobananas]

I agree with Mrs M, It shouldn't boost all the way to the end of the white if it's totally stock, check for dodgy 'mods'. Also when you buy a new motor its always best to check or replace anything servicable eg plugs, dizzy cap, rotor arm, fuel filter etc if you are unsure of their condition.

[s2esc]

the boost needle does not stay at the end of the guage, it reaches the end when fist on boost then drops to just under the end of the white. I was planing
on changing the plugs, all filters, oil and cam belt etc but i didn't know about the rotor arm is it an easy job? or is it best to get a haynes first.

also can anyone tell me what the black plastic air box on the front left side of the engine bay is? because one of the clips on the lid is broken. (could this be the problem)

[chriskay]

Which "left" is that? As you look at it from the front? If so, there's no air box there, as far as I know. There's a plastic box just rear of the washer filler cap with an air pipe from the back of the rad. If that's what you mean, that's where the ECU lives & should have a metal strap across the top. If that's been opened, it points to someone having played with the ECU, which could account for the high boost reading.
Cheers, Chris.

[Mrsmopp]

Sounds like you may have a bleed valve on or something similar and you are suffering from overboost to me. A stock T5 boosts to about 1/2 to 1/3 of the way into the white and shouldn't be spiking to the end of the white.

x

[LeeT5]

Hi everyone im a new member and am new to t5's aswell (just got mine yesterday). My problem is that my t5 drives fine when taking your time but when you put your foot down it stutters a bit in low gears (1\2\3) but its not to bad. but when you get up to about 80 ish and your in 4th or 5th gear and you floor it it stutters hard untill you get to about 4000 rpm ish then it pulls like hell again. any help would be much appreciated thanx.

WELCOME!!!!

Dont always assume the worst, i come across probs like this every day (AA Patrol). Anyway fault sounds very much like misfire probs due to a weak spark. IE, on tick over the engine is not working so it will idle ok but when you accelerate the misfire rears its ugly head because the spark is being made to work harder under load! when you ease off the throttle it probably dissapears? anyway this is a common fault with cars that arent looked after and have dirty, oily engines cos they attract the moisture and dont dry out.

Do as some people have said and change the plugs but make sure you also replace HT leads, dizzy cap, rotor arm. Replace the oil and filter, air filter and dont forget the all important cambelt AND tensioners.

It wont cost you much but WILL make a significant difference and improve fuel economy too.

If by some bad luck the fault still occurs then you have a problem that will need a competent mechanic/technician to road test.

IMPORTANT:: :nono: Do not drive it with this problem cos it could do lots of damage to exhaust components and internal engine components. I would of thought with a vacuum leak you would not get any boost and you most certainly would have the lambda light on because of running lean.

Clean your engine with a degreaser (cost about £5 from halfrauds) and jet wash your engine till it sparkles. :bath:

Good luck man!!

[s2esc]

over the next week or so i should have time to do a full service as advised. but tomorow i should hopefully have time to change the plugs and have a good look at whats under the bonnet to see if there is a bleed valve or anything else suspect under there because there is no metal strap on the ecu box and one of the
small plastic catch bits on the box has been ripped off (the awkward one near the wing) looks like an idiot may have been in there!!. hope not......