Hey guys,
Got a bit of an issue with my p75 engine (in my panda 4x4)

so ive not driven or used Fallout for about 10 months. the last time i used it, it was fine. i have occasionally started it to move it around where it is parked up.
a few days ago i have had to move it and oh.. somethings not right.

so when i try to throttle it up it misfiring and back firing and takes a while to "spool" up to the desired RPM. its like it injecting way to much fuel..
the fault does not go away no matter what temp the engine is.

i have a vacuum gauge fitted that tells me its.. ok. (its never had a great vacuum always sits in the "drive" rather than "idle" location.) never been an issue before.

there was a perished vacuum pipe going to the MAP that i fixed. other vacuum pipes checked with no leaks.

i am using a generic in line fuel pump (that has given me no issues before)

the timing marks all line up fine (not long had the timing belt, water pump and other things changed been driving fine before parking it up)

i have been told the temp sensor can give some interesting issues? is this the one on the back of the intake manifold?
does it have an air temp sensor that could also give issues?

and for those who wonder what project fallout is..

- Project Fallout


Thanks guys!

yes coolant temp sender can mess up fuelling, and yes its the one on the inlet. can test this with the old pan of water and measure resistance against temps.. This will mess the fuelling up if its gone, they usually go really rich but not known one to make it throw so much fuel in it doesnt run properly.... Unless its been dodgy for ages and its coked up the plugs and now after sitting for ages it dont wanna run properly - if thats the case just cleaning the plugs should make it run - obviously not a fix but would help diagnose.

air intake temp is on the throttle body itself, not heard of one of these failing before but they arent young anymore.. not actually sure how this not working would effect the ecu and running of the car as i've not known one to fail lol.

I'd be inclined to try another crank position sensor if you have one lying about - or can grab one off something at work. They usually start giving weird readings before they completely fail - sometimes it will run like a bag of rubbish when cold and start to clear as it warms but more common is that it works fine cold and then its signal gets worse as it gets hot - had both instances happen to me, in all instances the ecu usually has logged multiple random misfires but no actual sensors errors or anythingm do you have an engine management light wired up? - it tends to just take what the crank sensor tells it as gospel - never seen a code for it failing bar if its gone completely open circuit but normally the car has stopped working properly way before that happens.

yeah i get no "injector light" (got a code light sometimes but thats due to a very flat battery.)
ill check that CPS and coolant temp sensor. swap them over with something else for how hard they are to do.
(may the gods of old and new know, how much i enjoy working on these cars compared to these crazy modern things!)

come to think of it, its always ran really rich. hmm.. always had a not so great vacuum too (yet i have never found any leaks.. i even vacuum tested the manifold and throttle body using an aircon vacuum pump.. it held a vacuum ok! i know theres no leaks!)

Thank you Mr. blu

no worries chap, the crank sensor rarely throws a code as i say, it might log the misfires but an actual light and sensor code is super rare, so go there if the temp sender is working. You are a pro tinkerer so i dont really need to tell you but for others reading and thinking this is similar to my issue - do whip the plugs out and clean them as they will be coked up bad if its been running rich for a while

might be worth unplugging the lambda sensor and seeing if that affects things, I had rough idle and other problems a while back that were caused by that. Also throttle position sensor, and Idle Control Valve if you haven't checked them already.
Crank position sensor also went more recently; engine was struggling to start and stalling whilst sitting in traffic. Mine was pretty cheap during a standard Euro Car Parts sale, might be worth a shout

Good luck!

lambda shouldnt ever affect a cold start though, its open loop when cold and only goes into closed loop once its warmed a bit. should start fine and then suddenly run like a bag of nails when it switches to closed loop..

Re-reading the original post i'm banking on the crank sensor, if its misfiring etc then it has to be firing at the wrong time, which really is crank sensor erroneous readings or the timings jumped. Nothing else mentioned yet would explain it misfiring at all