luxembourgrst

lol after i was traying to get my 5th injector fuel maper working , i had the car at idle like 2000 rpm and then played with the map fueler somtimes he injected fuel somtimes not (because ther was a faulty connection on the map ) the AFR somtimes hit the 9.1 the engine always was on the point to cut off

then i cut the engine off a tried to restart it and impossible no signal of the engine no idle at all

after inspection spark was there new spark plugs fuel injector works (with the flap on the meetering unit down)....

then i took my cross over pipe off and saw like a little pool of fuel on the pipe where my dump valve is fixed

also found a lot off in the pipe who goes from the turbo to the intercooler

took the pipe off and a big flow of fuel went out my FULL INTERCOOLER was filled with fuel .....

i played so mutch with this 5th injector that he injected fuel in all my system

well little sorry only hope that it is this the problem that the engine didn t start

matthart

you might want to check your oil aswell, if you've put that much fuel into the engine it could well have got into the sump from flooding

Dubs44

iTrader: (1)

you need to stop pissing in the wind with mfi and 5th injectors and put some decent management on it imo

Chas

Not the case IMO ; It's not treating Porker 924/930 (911) owners that badly , but I agree that EFI is a better solution if it is done right.

Any management can overfuel with little know how ; yesterday I saw a Rover SD1 V8 on Megasquirt fuel between 11:1 and 9.5:1 on the dyno and that was with a previously 'working' AFR gauge. The black smoke from it was laughable. What was amazing was that he was seeing 25MPG on his daily commute! The carb'd V8 in an MGB? 13.7:1. Yes, EFI is always better without question...

Whilst mine is not as slick as some EFI systems my KE with an MF2 is fine ; If I am honest it is a nicer and more reliable drive than my 944 Turbo was with 'superior' Bosch Motronic injection ; it's not randomly losing power on occasions for one.

What someone said here before was spot on. Get the MFI working first. If then there is an issue with a couple of bits on then I would then consider going to a modern EFI setup. If not get it tuned first (preferably by someone who knows what they are doing) and then work on sorting the MF2.

It sounds like in your case the electrical connections are not all that which will not help anything at all. What are you using to judge your AFR?

Dubs44

iTrader: (1)

personally i'd rather not gamble an engine in the hope that the stone age management and a bodged on extra injector can cope with it, its old hat now, theres much better and safer ways to fuel an engine these days. if you're a stickler for keeping the car on the factory management thats fair enough but imo mfi is too temperamental when you try and ask it to do too much

luxembourgrst

How can the fuel enter into the oil. From wich way?

Dubs44

iTrader: (1)

past the rings and into the sump mate

luxembourgrst

past thepiston rings well fuel in the oïl is not do good i thing

but i thing there is not mutch who get into the oïl i have new piston rings on it

Chas

I see you missed my point and the examples I pointed with EFI etc.. I could carry this on for ages but I shall leave it at this seeing as it is pointless saying anything that adheres to the modus operandi here. Yes, EFI is potentially ultimately better than an carbs or basic injection for a variety of reasons (knock detection, better ignition and fuel control as only a few things). I say potentially because without the know how, any fuelling system is rubbish, no matter how many failsafes and benefits it can bring.

Maybe it's me but there seem to be more threads here recently about EFI going wrong that a 'bodged' K-Jet system .

If the oil is thinned down enough by the oil it will eventually get past the piston rings which in turn is not great for engine wear! This on modern diesels with a DPF is a big problem when they come to regenerate, often resulting with the cars dieselling themselves to destruction as a result of the sump filling up with oil.

luxembourgrst

well i going to look with my dipstik if the oïl niveau is higher or smells like fuel

Dubs44

iTrader: (1)

i see your point mate, any management working properly can be reliable. i know plenty of people running mfi with no problems at around the 180 bhp mark, but my point was as soon as you start trying to get over 200 bhp and beyond they become very temperamental in my experience. at this point you need to be looking at alternative management to provide safer more reliable fueling. the reason you don't see many threads about high power ke-jet cars and 5th injectors going wrong is because not many people bother with it anymore,

anyway the mfi efi debate is as old as the hills so i'll agree to disagree on this one

Chas

I think I can do that as well .

Rob_DOHC

iTrader: (4)

Which ever way you look at it a K type injection system is a mechanical device which wears out. The newest of which is some 20 years old. More people than I can count have had issues with mechanical fuel injection systems right from the TR6 through to Porsche 924's.

An ECU is a purely electrical device, it does not wear out. Once a calibration is set it stays. I am not saying auxiliary items can't fail, wiring looms, coils, injectors or that the calibration is well done but that is also true of MFI. Unfortunately with MFI once a calibration in set it is able to drift.

The KE-Jetronic was a marvel of engineering, sadly one which was instantly bettered and superseded by EFI.

So whilst I have a soft spot for MFI I just can't agree that it is in any way better than EFI, in terms of simplicity to accurately tune, vehicle consumption, drivability, emissions, reliability, consistency.... the list goes on.

I'm not trying to be a dick at all, I'm just giving reasoned facts, and when it comes right down to it either system can be badly setup


Rob,

Rob_DOHC

iTrader: (4)

Check your oil. Smell it.

It sounds like your 5th injector might have been stuck open, injecting constantly to fill up the cross over pipe and intercooler. Remove it and start again.

Adjust your MFI to give good fuelling for low boost, set boost to 12psi and concentrate on the MFI unit.

Then refit the 5th injector and slowly increase boost while adjusting the 5th injector. You should achieve and AFR of 14 at idle and cruise and 12 on boost but ONLY if you work methodically one part at a time.

luxembourgrst

well i have 14.7 at idle and cruising like 14.7 - 15.3
and i have like 20psi max boost

what AFR on : 7psi ?
then on : 14 psi?
and last :20 psi (think 11.00 AFR)

Rob_DOHC

iTrader: (4)

So your running at 20psi, lean and with a difficult to setup 5th injector? How you haven't destroyed your engine yet is totally beyond me. Take the advice offered freely here.

Lower your boost, as much as possible using the waste gate. Try to achieve reasonable fuelling with a boost level of less than 14psi BEFORE trying to achieve good fuelling at 20PSI. Don't walk before you can run.

20 PSI will mean the transient area you are probably struggling to tune will be of very short duration, you won't be able to twiddle your little pots fast enough or with enough accuracy to even begin to tune for anything less than full boost or more than cruise. Life is much simpler on a dyno where you can induce a constant load and hold it until you have achieved the correct AFR, you have a lot of time at specific load points. Unfortunately tuning on the road with out being able to take data logs whilst you have to adjust wanky potentiometers is going to be a long case of trial end error as in most cases it is impossible to accurately maintain or return to a specific load point.

Hence, low boost. Do a run and watch your afr... adjust 5th injector.... do a run and watch afr... adjust 5th injector

This makes sure its all working as you expect and give you an opportunity to learn how to adjust it properly in a slightly safer (for you and the engine) environment.

Rob_DOHC

iTrader: (4)

AFR wise it really depends on what you are trying to do.

For initial tuning aim for an AFR of 13, dropping down to 12.5 ish after peak torque for very low boost ie, less than 7psi.

Aim for 12.5 dropping to 11.8 ish for under 14psi

I personally prefer higher AFR's for high boost than most people as long as the engine is not knock limited etc. for 18psi I try to achieve an AFR closer to 12, normally 11.5.

For track cars or cars which are likely to be at high load for long durations I go much richer to cool the combustion chamber, at the expense of oil life, power and engine life.

This works for me, different people do different things.


But for you, I would start off by aiming for an AFR of 12 at any boost level. You can make it leaner or richer later...

Karl @ FPT

Please take Rob's advice before any damage is done mate.

luxembourgrst

yes tanks ROB

luxembourgrst

my injector was staying on all the time tink the transistor on the fuel driver is death

also had fuel in the oïl sump

put it all out and let it dry...