PeteMck

tps calibrated and flood clear off. Foot well clear of accelerator

Hi Guys, Having trouble with my megasquirt. It's a rover 4.6v8 When I crank I get a spark, when I turn the ignition on it the injectors fire 2 priming pulses. However while cranking the fuel pump runs fine but the injectors stop opening, and so obviously it won't start. from this I'm ASSUMING that the wires for the injectors are correct, the edis module is wired in correctly as its making a spark and that the msq module is getting a signal from the edis 8 module as the fuel pump is running and I'm getting an rpm of around 350. Any suggestions? I'm guessing one of my assumptions is wrong? Thanks in advance for any help

yer but was kinda hoping to find something majorly wrong. actually looks in pretty good nick. getting the heads pressure tested and stuff and then put it back together and then hope i discover my mistake with msq as i put it all back together. :s problem is i dont know that the engine actually ran when i got it. ah u live and u learn.

Hi Guys, Sorry there have been no replies. Didnt mean to be rube but i havnt been on here in a while due to work and as such havnt progressed much with the landy either. Megasquirt still isnt running. Got annoyed with that and got round to doing a compression test and 2 cylinders had dramatically lower readings so against everyone saying get it running before stripping, ive started to strip it down. hopfully get it back together in a couple of weeks and then ill no its a problem with my wiring.. you never no i might even stumble accross it when i put it back together..

I've been going at this v8 as and when for 18 months. I'm sure I can wait a couple more. Just as long as it isn't another 18! As for leads yer I've checked them many a time. As long as the diagram I'm using is correct of course!

No am going to do that before I start pulling it apart. The oil in the pistons to me suggests there is a problem somewhere that while might not be the reason starting is going to need addressing at some point. So in my head was thinking if I do a rebuild then a) I'll know that all the rings shells etc are new, b) if it is the problem I could be chasing wires and things around for ever c) to get an overall idea of the condition inside.

We'll see this is why I was planning on stripping it down. I've never had it running and due to work commitments and it being 50miles from where I live I've had the engine for 18months and I don't no how long the engine had been sat around before or why it was removed. So was always planning at some point to do things like rings and shells etc just so I know what sate they are all in. The oil was what made me think that something was up other than m/s. Especially as some pistons are noticeably worse than others.

No easy start does not help. Yer no sorry by behind I meant the gap was 5 teeth ahead. Sensor is also pretty much as close as I could get it.

the sensor is 5 teeth behind the gap. Worked out tdc by sticking a bolt in the spark plug hole and seeing where the point it was pushed up the most. If that makes sense. :s

Is that likely to be the trigger wheel causing that?

Can't do pics unless someone else on here can supply one. It just bends over and pushes onto a small outlet from the silver plate for want of a better word the plenum bolts to of that makes sense. Could the advance be causing this spark timing issue.

It goes into the plenum

Ok the little pipe is the one off there. Plenum is the 4.6.

The little pipe which comes off the plenum sorry to the regulator have put a t piece in that. Would take pics but 45miles from the vehicle at the moment.

The thing with this engine is I don't no for sure that it actually ran before. (That would have made life to simple)

Ok. Pump primes fine and cuts out after 2secs. Plugs are brand new Bosch. Map pipe is connected and is between manifold and fuel pressure regulator. Tested plugs and leads and they all spark. Wouldn't say it was big F/O but it's a reasonable spark. I know it's fuelling when cranking as well. also it blows back through the plenum sometimes. :s. Tried using a bit of easy start and it turned the air inlet pipe into a flame thrower :s

Closed value was around 20 and high was up around 250 maybe just under. Also how much harder will it make it to start without the pmw valve?

Ok. So the engine was almost starting. Would catch several times and for a split second you would think it had started but no joy. Took all the spark plugs out to look at them and there is a fair amount of oil getting into the cylinders. So the plan of action is to pull the engine out strip it down and replace piston rings, bearing shells and everything while I'm doing it and try and identify why there is all this oil in there. At the end of the day if it's that that is causing the problems or not there is enough oil on the tips of the plugs that something is definitely not right. They are pretty cover after a few cranks. Also noticed a build up of quite a lot oil round the butterfly valve in the plenum since trying to start it. Is this normal? Final question, on the bottom of the plenum housing there is the de-icer, one pipe comes out the block where should the other outlet be run to?

ok, TPS sorted now. still not started but least we are making progress.

the two i have when i put them on and click get value i get 7 for the closed value and 64 for the open regardless of which sensor im using. Yer i think i probably have it wired in wrong.

which wires go where on that, as the diagram i have shows middle wires as being green and is the earth. :S

dont no if it makes a difference but is a 4.6 GEMS sensor

yup gives 7 closed and 64 open. Have tried 2 sensors and they both give the same reading and both will reach 250+ if u turn them with a screwdriver. Is there a chance the MSQ isnt interpreting the signal correctly? have tried wiggling (i know its technical) but it doesnt change the value at all so semi ruled out poor connection but cant see what else it can be.... I dont see how i can have 2 faulty sensors that both give identical readings?

just actually bothered to read the above post properly and obvs the values are wrong. any ideas why?

ok, so replaced the TPS sensor with a brand new one and now get a value of 6/7 for closed and 64 for fully open. engine now turns over and catches and almost starts but not quite (and is now flooded). the middle wire i have as the earth, the red is the +5V which it is receiving and then the yellow for the other one. Tried the red and yellow the other way round and it gives a negative difference (i.e. closed value is higher than open). Is the flood clear value of 170 a direct value compared to the TPS so if the TPS value goes over 170 it stops it or is it more complicated, otherwise it seems i have bought a dodgy sensor or ive wired something wrong with it. :S this is starting to become very frustrating..... lol.