overfueling issue! - please help really short of time

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crossie
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Post Mon Oct 01, 2012 9:09 pm

e36 m3 engine into e30 m3

wired up and running

but running so rich!

E36 m3 engine was in a car and I drove it for a year and it ran well and not rich!

now fitted in e30

I havent been able to find a fuel pressure regulater on the e36 engine - should it have one?(I never removed one when I did the swap)

currently have the e30m3 pump feeding a swirl pot and then a e36 m3 pump feeding the engine
both are hard wired on a switch

have had both lambda sensors swapped for new ones

anyone got any ideas what the problem could be
HenryM3
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Post Mon Oct 01, 2012 10:16 pm

Coolant Temperature sensor, are all the plugs black, leaking injector?
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ajay
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Post Mon Oct 01, 2012 10:27 pm

I belive this or similar simptoms can appear to happen if the engine loses the road speed signal, the ecu then uses the tps as a rough guide a sort of un tuned alpha n allowing you to drive but not great, resulting in poor fueling. Just a posibility to explore, i had this same problem and was told by Sal at Evolve NOT to drive it hard and get it sorted as it could cause engine damage. Bexley motor works diagnosed mine as a faulty air mass and crank or cam sensor (can,t quite remember) but decided to put it on their rollers full chat 7300rpm a few times(without my knowlege) IIt died! But thats another story LOL! Just sharing my experience with a s50 3.0ltr E30 with the same problem, a few posibilities for you to explore. GL
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crossie
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Post Mon Oct 01, 2012 10:47 pm

road speed signal
is this the diff sensor?

faulty cam or air mass sounds about right
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ajay
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Post Mon Oct 01, 2012 11:01 pm

The road speed signal comes from the diff and should go to the instrument cluster (speedo) and to your s50 engine/ecu. Check its going to the engine, i don,t remember the pin numbers/colours but maybe you still have your wiring diagram or find out from the person who done your loom. If your not sure maybe you could unplug the wire from the diff and drive for short period, does it drive/sound exactly the same or worse? you may also need to clear ecu faults with something like a peake reasearch reset tool this can also give you fault codes that appear.
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crossie
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Post Tue Oct 02, 2012 7:18 am

cleared the codes last night

lambda sensors was on there -they are both new

also road speed sensor

dash speedeo works
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ajay
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Post Tue Oct 02, 2012 3:01 pm

Have you drove the car since? Drive for a bit and re check the codes, what comes up?
Speedtouch
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Post Tue Oct 02, 2012 3:11 pm

May be worth trying a different chip in the ECU. I have one available for the S50B30.
///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
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crossie
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Post Tue Oct 02, 2012 9:01 pm

CHEERS FOR THE HELP GUYS

no ecu speed signal wire - now fitted - running better but still rich


video of computer read out -





sorry its on its side!

Any other ideas
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ajay
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Post Tue Oct 02, 2012 10:12 pm

Double check the lambda sensors are plugged in the correct sides of the manifold down pipes ie (1 sensor monitors 1-3 the other 4-6) if you have them accidentally reversed the ecu may make adjustments for 1-3 but could actually be reading 4-6 and visa versa, subsequently never actually adjusting correctly, or at least i think. Also make sure every time you unplug/plug something in or out with the engine running,you clear the codes. What codes are up at the moment?
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crossie
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Post Wed Oct 03, 2012 7:42 am

lambda sensors are the only codes last night

Thanks
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crossie
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Post Wed Oct 03, 2012 10:10 pm

no progress this evening
tested the lambdas again

it seem that the back half of the engine is whats at fault

anyone got any idea what will make the front have run rich and the back half run lean??
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crossie
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Post Thu Oct 04, 2012 12:48 pm

come on guys any ideas?
HenryM3
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Post Thu Oct 04, 2012 9:35 pm

you need to check the fuel pressure is 3.0bar +/- 0.2 with engine off and that it varies between .4 and .7 bar lower with the engine running. when vacuum removed from regulator the pressure should rise. if this is good then check that the injectors are pulsing on those 3 rich cylinders.
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crossie
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Post Thu Oct 04, 2012 9:35 pm

Cheers to those that posted
Hopefully fixed
Mate spotted a simple mistake tonight
Off to Nurburgring tomorrow now due to missing the ferry
Said mate running late!
HenryM3
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Post Thu Oct 04, 2012 10:06 pm

Re-reading your first post, depending on the date of your engine, the pressure regulator is either on the end of the fuel rail or it was underneath the origional car around the area of the fuel filter. not actually sure if the car would run at all if you didn't have a regulator fitted?
HenryM3
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Post Thu Oct 04, 2012 10:09 pm

For all the people that did bother to post, perhaps you could share your mates simple fix.
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crossie
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Post Sat Oct 06, 2012 8:26 pm

cylinder 5 and 6 had the leads on the wrong way!
must learn to read the lead numbers!