Rough running ANY advice?
Turbo Mini Forums

Not long had my car but did a fairly long run from mine to mini spares brum approx 30 miles each way. Previously it was running fine but bogging down slightly in 4th. On the way it mis-fired a couple of times then cleared itself. Coming home at a steady 50-60 it lost power which felt like fuel starvation this happened in every gear. When I pulled over it would rev freely. I turned it off then on again and it was ok for another 10 miles then same again.
As I've said in other posts I don't really know much about the engine it's said to be a 1380 turbo with omega pistons uprated cam, valves rocker etc. it has an electric fuel pump and regulator and I've established a 1275 electric dizzy. Also ngk bpr6es plugs which look a bit brown at the electrode.
I have driven it through a big rain storm... Not sure if water has got in somewhere?!
Also I've put two tanks of shell optimax in and I've heard this is no good for these engines?
I'm thinking I need to drain the fuel and replace with 95 Ron. Check the timing and valve clearances. I'm not sure about the dizzy and plug setup I'm thinking of fitting the Aldon Amethyst box but I'm not sure if I need to upgrade the dizzy first?!
Any help and advice would be greatly appreciated!

Check fuel pressure and filters, ignition timing (dizzy may be loose), brown plugs are a good indication. Pull off the dizzy cap and dry out the inside with a hairdryer or something, replace the coil maybe if none of those solve it.

Any missfires under boost is usually caused by a lean mixture, have you got a AEM lambda. Air fuel gauge it to tell you where you are?

Do a compression test to see what's what, you need all the octain you can get so optimax is great,
Which joker told you optimax is bad for a Turbo engine

yup what steve says , optimax is good stuff. if its a points distributor also check the condenser. but dirty rust in the tank blocking the pickup may be going on .

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

As said sounds lean. I was having intermittent fueling problems with my turbo motor which i have now hopefully sorted. Without the aem i would have wrecked my engine without doubt!!

Thanks for the replies! Got a few more things to check then. There is no in line fuel filter would it be worth fitting one? If so where? Between tank and pump or before the FPR?

in a perfect world Before FPR under the bonnet ........... a AEM lambda gauge is a must!............ have a look here http://www.ebay.co.uk/itm/AEM-Wideband-AFR...=item1c3474989e

Looks like a lambda guage would be a good buy! Bit pricey though! Are they easy to fit? Where do you mount the sensor? Looks like I've got the bug and my credit cards gonna take a hammering!

Quick update if your interested got to the root of the problem it seems the inlet manifold is blowing! Engine out next week and a new gasket on. It'll give me a chance to spruce up the engine bay then.