No boost from Primary Turbo

[Marky B]

It started last week, I get great full boost on second turbo but nothing on the first. I can hear a slight rattle from the downpipe area on idle, which disappears after 1800 rpm and there\'s a spinning noise from the first tubby - like it\'s spooling up (a bit rougher than the normal whistle) but no boost ever comes. From this I suspected the turbo itself, however It must be producing some presure as it is presurising the system enough to allow the second turbo to kick in??? or is this wrong?

A little while ago I swapped over all the vac pipes for new ones an changed 2 solenoids that I\'d broke the ends off with the brittle pipes. Everything was fine to start with, then I found if I floored it off the mark, I would get boost from the first turbo but nothing in the second and a loud "wooooo" from under the bonnet when I let off the throttle, if I then reved the engine once in neutral, then put it in gear it would pull as usual through the rest of the gears. I\'ve now begun getting boost problems with the first turbo,. Now I get nothing till midrange, then a massive boost no matter how I drive it. The hose I used when I replaced the vac pipes was slightly thinner on the inside diameter than the stock pipeing, does this matter???

I have checked the pipes thoroughly twice and there are no Kinks, splits or gaps so the only thing I could think of is the inside diameter of the pipes is not allowing enough presure through. I was VERY carefull when I replaced them, doing one at at a time and I am 99.9% sure they are correct (besides it did run fine to start with).  I have a couple of spare solenoids here, so I could try swapping them at a weekend if anyone suspects a particular one or two from the symptoms I\'ve described? Any Idea\'s anyone as I\'m running out of options an 2 + heads are always better than one  

Thanks

Mark

[Bobfish]

second turbo won\'t come on unless the first turbo is producing 8psi or more.

Sounds like youve routed a pipe or something wrong, got a check valve the wrong way round or have a fualty solenoid. Smaller ID pipes wont make any difference really, there isnt alot of flow through the pipes.

Check and double check your vac line routing....also it would help if you could provide us with results if boost test (third gear, floor it from 2k, list boost levels at 2k, 2.5k, 3k, 4k, 4.5k, 5k 6k etc)

however, dont do a boost test if the car doesnt feel right - if its missing or anything.

How long since your last spark plug change?

[Marky B]

If the pipes are wrong why would it runright initially? Plugs were changed around Christmas, Cheers I will do a boost testtoday and post the results after 6 tonight.

Mark

[Bobfish]

your right about that marky. How many miles since christmas? Any results on that boost test?

[ro284]

Did you replace the pipes with restrictor pills in the actuator pipes Mark, refitting the pills? don\'t know enough about this i\'m afraid, just a thought.
Bob

[Marky B]

AAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHH,  the next night it was dry enough to do the boost test, I staerted her up an let her warm up outside work as usual, I took her down the road and the first turbo came in ! :xconfused

The rattle was still there, but I was gratefull it was working ok. then I puled out of the petrol station tonight and it all went pear shaped, exhaust not changed, I can here at least one of the tubbys spinning up, but I get no boost from either now :Grrr

Think I\'m gonna have to go see pip  again lol.

Mark

[Bobfish]

If you want some advice mate give me a call, i dont mind telling ya what to check. 07977 015 912.