Remapped with boost issues........

[850T5 Jason]

Hello, its been a while since ive been on here so its good to say hello! hope all is well

Right i hope you can help or have something to say and apologies if this has been covered before

I recently fitted a remapped ecu to my 850 T5 as i used to run a MBC before, i had no problems before but i was looking for more power and i really wanted the ecu to have a say in what's going on safely using the stock solenoid again.
The problem im having is with the new ECU is the boost is very odd and doesn't want to hold, it will hit 16.5psi under load but it falls of as the revs climb to around 12 psi @ 5000rpm where it holds which is what i was running before with the MBC.
And most oddly if you give it the beans from 1st gear and go through the gears or boot it from higher revs it never goes above 12 psi no matter what even if you come off the pedal and reapply in any gear, although the boost is totally stable at 12psi while going through the gears. The only way to hit 16psi is if im in second or higher from lowish revs and it may hold for 1000rpm-1500rpm or so once its peaked and the difference in pull is huge!

Any ideas or thoughts???

The car runs a brand new turbo with a 16T compressor wheel, full de-catted exhaust, panel filter and before the remap i had it rolling roaded to check its health. it ran 240bhp and 253lb/sf of torque @ 12.5psi boost dropping to around 11psi @ the rev limit so no issues there and i was happy with the results. Im also now running on 97RON since the map for safety.
The boost piping and vac piping is all new as its just been replaced and with the turbo being new i cant see it being actuator related.....

do the stock recirculating valves leak @ higher boost/revs???? as this is my best guess as to why it wont hold boost, does anybody have the same issue?? i really would have thought it could have at least held 15psi through the revs surely ??

Its also worth me mentioning that i tried the MBC i ran before set at 16psi and it spikes to 16 and then just drops of rapidly to around 12 once again ;/

any comments would be greatly appreciated thanks in advance

here are a few recent pics of the car as its changed a little since my last visit

thanks, Jason

[LiamT4]

Although the actuator is new and is working fine, has it been set up properly? It can be tightened/loosened to adjust the boost slightly. Possibly this may need tightening a bit.

[960kg]

I had this wavering of boost when i had my remap .....i threw away the silicon hoses and bought some proper Volvo hose and a new TCV and the problem went away. I have since fitted a new Forge recirculating valve to ensure no loss of extra boost. Boost now comes in very solid and holds.

[850T5 Jason]

Thank for the responses, ill check the actuator today and see what its opening at.

And ill see about getting hold of some better vac pipes, and i do have another boost solenoid i could try out. i may even see if i can blank of the recirculating valve just for a quick road test and see what happens. Ill be happy once i see that boost gauge needle holding better

960kg can i ask what boost yours runs and what it holds at in the higher revs??

many thanks

Jason

[theflyingbrick]

i had the same problem when i had mine remapped turns out my ecu was knackered money straight down the drain!!

[850T5 Jason]

hopefully that wont be the case for me fingers crossed!, im definitely being led to thinking its to do with the turbo because before i fitted the new turbo i ran the car in stock set up for a while and the boost was okay at 9.6psi etc, but just after i fitted the nee turbo i ran it stock again and this time the boost climbed very slowly upto around 9psi but fell a little to around 5-6psi :/

Ive been out with the car this morning and tested the actuator opening pressure and it appears to creep open around 2.5-3psi so it may very well need a little tweak up. Do you guys recommend tweaking it up to 4psi ish for testing it????

Also ive stripped of the recirculating valve and added an extra spring from an old dump valve, the new spring fits and seats perfectly without any danger of it damaging anything in operation. So the new spring should add another 5psi to the opening pressure of the recirculating valve
I would like to think ill get to road test it today but with the weather being so wet i doubt the 2nd and 3rd gear boost test are going to happen haha

thanks

Jason

[nuttyt5]

Ecu is the problem wot map have you installed I do no 3 maps that back there selva off its a safety issue wich can be removed but I doubt your engine would last that long I would recommend from wot I have done is to put mbc back on as the map is made to have mbc and adjust it for that

I put 3 turns on actuator and mbc on and you will soon notice a difference I mounted mbc in dash saved me getting out every 10 seconds let me no wot it does hopefully I can help as I map ecu,s To experiment

[850T5 Jason]

Ecu is the problem wot map have you installed I do no 3 maps that back there selva off its a safety issue wich can be removed but I doubt your engine would last that long I would recommend from wot I have done is to put mbc back on as the map is made to have mbc and adjust it for that

I put 3 turns on actuator and mbc on and you will soon notice a difference I mounted mbc in dash saved me getting out every 10 seconds let me no wot it does hopefully I can help as I map ecu,s To experiment

Hello. Thanks for the response

Im not sure whos map it is, i bought the ecu of eBay second hand, the guy had only ever used it with an MBC and had no problems and the ecu apparently was mapped in Sweden, I've driven the car today after fitting the extra spring to the recirculating valve and setting the actuator @ 3.5 psi and although it has made a slight difference its still pretty much the same dropping to 12psi at the end of the revs, after a second look the actuator was actually opening up the wastegate at 2psi. I'll try winding up the actuator and fit the MBC tomorrow as you say and let you know what happens. If its still the same with the MBC I'm going to be stumped :/

Many thanks

Jason

[smithy]

Set the actuator at 7.5 psi mate and turn your mbc down see how that is.

[850T5 Jason]

Set the actuator at 7.5 psi mate and turn your mbc down see how that is.

Ill try that today mate thankyou ill post up after the test run.

Jason

[850T5 Jason]

well things still not going well bloody cars!

right..... i set the actuator at 7.5 psi and refitted the MBC which is set at 16psi, it spikes then holds around 15psi till 4000k then drops to around 14 at 5000k then drops rapidly to 12.5ish after that :/ so something isnt right.

One thing i am thinking though is my MBC may well be no good, its a brass ball bearing type but its nearly all the way in to give me 16psi....maybe this isnt a high boost MBC????.....struggling to do the job??

Sadly i dont have another one to try out, the boost tailing off makes me think boost leak but im extremely confident that it isnt that due to the fact that there is no hissing or wooshing and all the pipes have recently been checked and replaced due to a previous boost leak.

I have a couple of options, one is to get a good MBC and try that to rule out my MBC being a little tierd... and two i have a rica 304 ecu coming so maybe set the actuator back to the factory 3 psi and fit the rica ecu ????? hhhmmm

anyone got a video of there boost gauge going through the gears??? on a mapped 850 T5??? id like to see a healthy one to see what im aiming for

thanks

Jason

[glock19]

Post a picture or diagram on how you route the MBC to the turbo. That should give us something to think about.
Seems to me your wastegate actuator is receiving most of the air from the compressor housing.

Edit : Wait a minute, saw in your signature that you are having a diesel ?

[850T5 Jason]

Post a picture or diagram on how you route the MBC to the turbo. That should give us something to think about.
Seems to me your wastegate actuator is receiving most of the air from the compressor housing.

Edit : Wait a minute, saw in your signature that you are having a diesel ?

Ill try and take a picture today but its simple enough to explain....the vac pipe comes straight off my compressor housing upto my MBC
Then straight to my actuator. Pipes are around the same length as stock solenoid piping. And ndn i dont drive a diesel :/ good old T5 petrol

Thanks
Jason

[850T5 Jason]

ive been out this morning and did a couple of videos of the boost gauge however these videos are a little crap! i did my best it easy to see the issue though -

you will see on my boost gauge each marker is 2psi so you will see it go upto 16psi in the first video in 3rd gear and drop down to around 13psi near the end of the revs (i didnt manage to take it right round the revs but that was to around 5000rpm so clearly dropping of to much already).
And in the 2nd video (poor video) the issue is far more clear with boost dropping of in 2nd rapidly and never really getting to 16psi as i hit 3rd and all these videos where done with the MBC fitted back on with the actuator set at 7psi. MBC set at 16psi as tested using a pump and gauge at home see what you guys think -

vid 1 filmed in 3rd gear upto 5000rpm



Many thanks

Jason

[850T5 Jason]

Vid 2 filmed from 2nd - 3rd gear

[nuttyt5]

Is this still on boost solinode if so have you got a spare? Or even better a phase 2 boost control solinode if not get the mbc on there and cut out the boost control solinode it's a pain I'm not closer I would come and help lol

[850T5 Jason]

Is this still on boost solinode if so have you got a spare? Or even better a phase 2 boost control solinode if not get the mbc on there and cut out the boost control solinode it's a pain I'm not closer I would come and help lol

Yeah that is a shame, thank you though

The videos where taken using my MBC, the issue is slightly worse using the stock solenoid

thanks

Jason

[960kg]

After watching your vids. i do believe your remap is not what you think it is!

You may have the lower 280 instead of the higher 304.

My own HLM304 will allow a 16psi as normal but then i can up it to 18 / 19psi and more or less hold it.

The 280 MAY only allow 16psi and no more due to being allowed to use although not recommended 95ron

The 304 is recommended to use 98 ron all the time.

Your guage is acting very similar to mine before my remap and that was 15psi max. and reduced to 10psi by the ECU. This was with an MBC but only just for seeing what happens.
I dislike MBC`s.

[850T5 Jason]

After watching your vids. i do believe your remap is not what you think it is!

You may have the lower 280 instead of the higher 304.

My own HLM304 will allow a 16psi as normal but then i can up it to 18 / 19psi and more or less hold it.

The 280 MAY only allow 16psi and no more due to being allowed to use although not recommended 95ron

The 304 is recommended to use 98 ron all the time.

Your guage is acting very similar to mine before my remap and that was 15psi max. and reduced to 10psi by the ECU. This was with an MBC but only just for seeing what happens.
I dislike MBC`s.

Thanks for the responce

I would tend to agree, although the map on this ecu is unknown other than it came from Sweeden and was claimed to be a stage 3 tune, clearly isnt though ha. i have a rica 304 coming hopefully next week

Also i run my car on 97 RON or 99 RON depending on the fuel station im at since fitting the remap so that should rule that out. And the videos where taken using the MBC so i would have thought that the ecu cannot back off the boost even it wanted too???

thanks

Jason

[oblark]

Fit the RICA 304, run it on 97/99 RON and throw the MBC in the bin.