205 cosworth 4x4 major engine cut
Discussion
Hi got a problem with my 205 dimma cosworth just wondering if any cosworth experts on here can help its a ma developments engine gt30 turbo wasted spark ignition autronics management tial external wastegate , when on full boost engine cuts and backfires momentarily if I feed power in more slowly it doesn't do it seems to get worse the longer its driven , also not sure if related but I get turbo flutter when accelerating ,I have changed boost controller because I thought it may have been over boosting but its still the same ,I have wondered whether the engine cant ingest the air that the turbos producing and is causing back pressure on the turbo if that makes sense ? any advise most welcome thanks
thanks for reply I have thought about putting fuel pressure gauge in to monitor pressure just to see if pressure drops on full boost
rhinochopig said:
Not a cossie expert but the 'cut' is typical of either a faulty fuel pressure sensor or poor fuel pressure. Can't help re the other issue.
ninjacost said:
,I have wondered whether the engine cant ingest the air that the turbos producing and is causing back pressure on the turbo if that makes sense ? any advise most welcome thanks
You can be sure that is not the problem.So has this setup run properly previously ? Have there been any changes since then ?
Has it been setup and mapped properly ?
Are the basics in good order. ie plugs, leads, and engine in general ?
Does it run properly at all other times ?
Is it an "overboost" limit on the EMS system? If you've got poor boost control, a rapid tip in may result in an overboost spike high enough to trigger and safety cut that might be calibrated. But a slow tip in will allow the boost control system to maintain sufficient control to avoid the limiter??
ok engine was mapped by mark sheard ma developments all the work was done prior to me buying car plugs are brand new leads perfect engine as done only 2500 miles general running is ok a little choppy at low speeds but I put that down to fuelling 1000cc injectors ? like I said on original post if I feed power in slowly it doesn't cut but if I give it a bootful of pedal as the boost increases more quickly it cuts
stevieturbo said:
You can be sure that is not the problem.
So has this setup run properly previously ? Have there been any changes since then ?
Has it been setup and mapped properly ?
Are the basics in good order. ie plugs, leads, and engine in general ?
Does it run properly at all other times ?
So has this setup run properly previously ? Have there been any changes since then ?
Has it been setup and mapped properly ?
Are the basics in good order. ie plugs, leads, and engine in general ?
Does it run properly at all other times ?
yes I have thought this but what would be causing the boost spike bearing in mind I have a new boost controller on identical to original , could turbo surge cause this ? i'm not a cosworth expert at all i have loads more experience with Peugeot engines
Max_Torque said:
Is it an "overboost" limit on the EMS system? If you've got poor boost control, a rapid tip in may result in an overboost spike high enough to trigger and safety cut that might be calibrated. But a slow tip in will allow the boost control system to maintain sufficient control to avoid the limiter??
boost on gauge hits 30 psi but that's gauges limit so it may well be going over that think I will be best to call Mark , im in uk yes car in question is well known dimma 205 H20 COS thanks for your input
stevieturbo said:
The obvious question is, what is the boost doing ? Is it stable or is it spiking ?
And is it running the boost level's the car was mapped for ?
It may be an overboost cut, but more info needed.
Or give Mark a shout on Monday. Are you local to him or are you even in the UK ?
And is it running the boost level's the car was mapped for ?
It may be an overboost cut, but more info needed.
Or give Mark a shout on Monday. Are you local to him or are you even in the UK ?
its a mac boost solenoid calibrated through the autronics ecu with a tial external wastegate with a 11psi spring if I run just on wastegate with controller disconnected I get no issues although the car is obviously a lot slower
Max_Torque said:
What make/type is the boost controller? And are the control terms calibratable?
You're going to blow it up.
The ecu sounds like it is setup to control boost....but then you're fitting some sort of other boost controller to it ?
And you seem happy to run the car when you know the boost gauge has been pegged at 30psi ?
Seriously, get the car to someone competent to sort it out before you do some very £££££ damage.
The ecu sounds like it is setup to control boost....but then you're fitting some sort of other boost controller to it ?
And you seem happy to run the car when you know the boost gauge has been pegged at 30psi ?
Seriously, get the car to someone competent to sort it out before you do some very £££££ damage.
Hey ? not sure what you mean the boost solenoid is controlled by the ecu I didn't fit anything it was on when I got the car as far as im aware it was fitted by ma developments I think engine is mapped to run 2.5bar of boost which is obviously over 30 psi im not happy to run it that's why im on here asking for advice thanks again :-)
stevieturbo said:
You're going to blow it up.
The ecu sounds like it is setup to control boost....but then you're fitting some sort of other boost controller to it ?
And you seem happy to run the car when you know the boost gauge has been pegged at 30psi ?
Seriously, get the car to someone competent to sort it out before you do some very £££££ damage.
The ecu sounds like it is setup to control boost....but then you're fitting some sort of other boost controller to it ?
And you seem happy to run the car when you know the boost gauge has been pegged at 30psi ?
Seriously, get the car to someone competent to sort it out before you do some very £££££ damage.
Sounds very much like what mine does when the plugs are a bit mucky. They stop firing at high boost, can almost play a tune by throttle position to bring the sparks on and off. Suggest you check the plugs by replacing them and gapping them quite tight (0.7mm). Gap is important on mine, 1mm gap causes spark blow out at around 12PSI on my rather lame coil packs.
sorry I meant solenoid mac type , the car is just shy of 500bhp so its going to be running a fair bit of boost sure Mark said 2.5bar ,will give mark a call :-)
stevieturbo said:
You said you fitted a new boost controller ?
Or do you simply mean you replaced the boost control solenoid ?
And I really doubt it is mapped to run 2.5bar.
Take the car to Mark before you do damage. There seem to be too many unknowns
Or do you simply mean you replaced the boost control solenoid ?
And I really doubt it is mapped to run 2.5bar.
Take the car to Mark before you do damage. There seem to be too many unknowns
Hi I did change solenoid to see if that was cause of problem ,its an identical one to previous , will call ma developments ,thanks for help
Max_Torque said:
Have you changed the boost control solenoid? Perhaps to one with a different orifice in it?
You should be able to see the demanded and actual boost by hooking up to the EMS system, even if the analogue gauge is max'd out.
You should be able to see the demanded and actual boost by hooking up to the EMS system, even if the analogue gauge is max'd out.
Hi swapped plugs for brand new set gapped as you say to 0.7mm but made no difference , thanks for reply
fatjon said:
Sounds very much like what mine does when the plugs are a bit mucky. They stop firing at high boost, can almost play a tune by throttle position to bring the sparks on and off. Suggest you check the plugs by replacing them and gapping them quite tight (0.7mm). Gap is important on mine, 1mm gap causes spark blow out at around 12PSI on my rather lame coil packs.
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