14 replies to this topic

[REVVIT]

Hi All after some technical imput on my none starting MPI..

Bit of background car has been of the road for over 20yrs in that time it has been completely restored using new refurbed or restored original parts body and mechanicals.I purchased the car December 2023 as an unfinished project. It had been built to look like a sportspack which i like but as i favour early cars i've spent the last few months making it look like a MK3 Coopers S..With the exterior looking how i like i turned my attention to making it run and this is where my problem lies..It simply will not run on its own..i can get it to run with a dash of brake cleaner but alone it just wont start...It has fuel at rail it has spark the injectors are new and tested and working..over the weekend i removed the engine harness and belled out every terminal all working ..the ecu and 5as have been checked and working,fuel pump is new and its at this point im at a loss of what to do next..I have also manually pulsed the injectors to simulate them opening and closing and the car will run suggesting the ecu/immob is possibly not opening them even though its been tested and proved to be ok.

Any suggestions will be much appreciated Thanks...

[Steve220]

Was the engine rebuilt or left alone?

[sonscar]

Just random thoughts.Have you connected the fuel pipes correctly regards feed and return?Doesn't hurt to check.Have you tested the fuel pressure?Research Noid light and check the injectors are firing.Steve..

[REVVIT]

Was the engine rebuilt or left alone?

Yes engine is a new Minisport engine kit 1293..gearbox built by Southam Mini Metro and the clutch has been fitted correctly..

[viz139]

Injectors require a camshaft sensor input so check the plug on the back of the block.

[REVVIT]

Just random thoughts.Have you connected the fuel pipes correctly regards feed and return?Doesn't hurt to check.Have you tested the fuel pressure?Research Noid light and check the injectors are firing.Steve..

Yes i have but im about to go over all the basics again..fuel pump is new but i will check and i have checked injectors with Noid tester and they work..even checked feed from ecu to trigger injectors and all working !!

[REVVIT]

Injectors require a camshaft sensor input so check the plug on the back of the block.

yes checked sensor and even replaced sensor all good ?

[mab01uk]

I posted this article linked below a while back, might have something useful to check.

 

Mini Mpi Diagnostics - Car Mechanics Magazine:-

https://www.theminif...zine/?p=1171123

Edited by mab01uk, 16 July 2024 - 10:58 AM.

[mpialan]

Ensure connectors to the ECU and Relay are clean and firmly attached. I have pulled the connectors on the ECU tight with a couple of cable ties on mine.

[Bobbins]

Is the fuel filter connected the correct way round?

[REVVIT]

Is the fuel filter connected the correct way round?

I will check this ..i had a quick look last night but car is so low i need to jack it up and have a proper look ..

[viz139]

If the car has been resprayed it may be worth double checking the earth under the expansion bottle on the LH inner wing. This earth feeds the ECU and most of the injection system.

[REVVIT]

Chasing my tail with this so just to eliminate new or faulty  parts i had never done a fuel pressure test as the pump is new so why should i !..Installed a pressure gauge inline of the fuel feed line and keyed ignition on pump primed pressure climbed to around 30 psi then immediatley dropped to zero ? Cranked as if to start engine and still zero pressure reading on gauge? Clearly something is wrong why no pressure ..?Fuel pressure regulator should restrict fuel flow so i gently clamped the fuel return pipe and i instantly had pressure ?..Again went for engine crank and it started instantly and held a steady pressure on gauge car running as it should..so after weeks of problem chasing it seems my pressure regulator isnt working..Ive noticed several mini suppliers sell a pressure regulator upgrade which is adjustable for MPI minis ..Has anyone experience with these or is it best to try and replace the standard one in the fuel rail...

[Bobbins]

An adjustable regulator is only an upgrade if you have reason to adjust it, usually because the mapping or engine spec demands it.

 

Personally, for a standard engine I'd fit the standard MPi regulator, it's one less thing to question if you have another problem in the future.

[REVVIT]

An adjustable regulator is only an upgrade if you have reason to adjust it, usually because the mapping or engine spec demands it.

 

Personally, for a standard engine I'd fit the standard MPi regulator, it's one less thing to question if you have another problem in the future.

Thanks...Im all for keeping it simple..the engine is a Minisport 1293 with head work Maniflow Lcb and exhaust nothing to spicy..