4.0 P38 turns over for ages before starting!

As per the title, when the rangie has been left over night or had a chance to cool down a bit it takes ages to start, it turn over fast and finally splutters into life. it stinks of petrol too.

If started hot it starts straight away.

Its almost as if the petrol is draining back to the tank but I'm unsure how to check for that.

Any clue where to start?

I'm glad to see my first 2 days of rangie ownership is living up to the expectations... if it didn't drive and feel so much better and unlike anything I've ever driven I'm not sure I'd put up with!

I can't see me feeling so fondly about these problems if it was say, a citreon...

get your self a new set of plugs befor it dont start at all. and look at the leads while your hands are dirty ..

temp sensor front passenger side of inlet manifold,not temp sender

Can't be certain about the plugs but the leads are new as pointed out by the previous owner when I looked at the car. He has also changed the inlet manifold at some point which might mean a possible bad replacement.

I'll go look for this sensor as its a nice evening... i shall return...

Are you for real? first you say it stinks of petrol when trying to start then you say you think it has lack of petrol as its draining back to the tank, which one is it?! Temporary fitting clear pipe would allow you to see if the fuel was draining back, not rocket science is it?

madst said:

Are you for real? first you say it stinks of petrol when trying to start then you say you think it has lack of petrol as its draining back to the tank, which one is it?! Temporary fitting clear pipe would allow you to see if the fuel was draining back, not rocket science is it?

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If I knew fella... would I be asking? I'll let you work that out as lets be honest, its not rocket science is it?

Anyhow despite useful comments like that, I checked for that sensor. theres two on the inlet at that point, a brown two pin and a single prong one just above. The clips broken on the brown one and for some reason its full of copper grease! Going to clean that up and try again in the morning as the lights going now.

the brown one is the one to check it alters fuel like choke on carb for starting

Thats sounds like the culprit!

daft question but does anyone know if they are diffent between 4.0 and 4.6 as the previous owner fittted a 4.6 inlet mani.

I'll give it a good clean and try and figure out a way to keep it attached! may have to try and get another plug and splice it into the wiring.

Why don't you measure the voltage of each wire on sensor when its cold and then when its hot and compare difference to see if its working correctly.

Good idea

I had a spare in the 4.0 inlet manifold that came with the car so swapped them over this morning but it hasn't changed a thing.

Now unless both sensors are knackered it could be another problem or theres a problem in the wiring. Does anyone know what sort of values I should be looking for at cold and warm to confirm the wiring is ok?

I had the same problem,changed the coolant temp sensor even if it didn't register a fault and for now it is cured.replace it coz it tends to have a coat of calsius on top of the coper,replace the plug also like i did,it is a sheap thing to do.otherwise soon u will replace ur starter motor and cats.

I would imagine with plug disconnected (ignition on) you should have 5 volts on one wire and an earth on the other. With sensor connected and when engine cold I would think about 3 ish volts and should drop steadly as engine warms up. The other wire should be an earth so should read 0 volts at all times.

Well, checked both sensors today

Decided to measured the resistance on the one in the inlet manifold with a hot engine then the cold spare one in the garage.

swapped them over and repeated the check a few hours later so I could compared the reading after getting the engine hot and they were both reading roughly the same in both states.

If I can read my scribbles right - 2.3 ohms hot and 0.8 cold and both were reacting when heated or chilled.

To be honest, think the sensor is only a couple of quid so i'll go with you jorjio and I'm just going to replace it anyway just to elimiate any problem.

Didn't get a chance to check the wiring yet but some signal is getting through as if you pull the plug and turn her over she won't start at all.

I'm wondering if I have a bad earth or something.

Anything else I should check guys and gals?

j the range said:

get your self a new set of plugs befor it dont start at all. and look at the leads while your hands are dirty ..

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Update time.
New sensor, new plugs and leads and still no difference...

Any more ideas folks as this is starting to drive me nuts...

its maf

Well I tried a quick test with the MAF, started the car and pulled the plug and it just spluttered away. Plugged it back in and it picked up but tried to idle at 300rpm and then cut out. restarted her and she returned to normal. Also gave it a clean with a little carb cleaner. Seems to be fine to me

The rangie runs and idles perfect onces she finally starts. Its even giving reasonable MPG

I got a pal to plug in his MSV faultmate and the only fault was the knock sensor. Cleared the fault and waited for her to cool back down again. Restarted her again with the same problem, plugged in the MSV and no fault codes present... going to try again in a weeks time and see if anything has popped back up again.

Anyone else got any ideas what else to check?

A long cranking time when cold. Easier to start when hot and runs okay. I assume your P38 has a fuel filter [near the fuel tank?] and your symptoms sound like it is blocked? When did you change it last?

Frostycab said:

Well I tried a quick test with the MAF, started the car and pulled the plug and it just spluttered away. Plugged it back in and it picked up but tried to idle at 300rpm and then cut out. restarted her and she returned to normal. Also gave it a clean with a little carb cleaner. Seems to be fine to me

The rangie runs and idles perfect onces she finally starts. Its even giving reasonable MPG

I got a pal to plug in his MSV faultmate and the only fault was the knock sensor. Cleared the fault and waited for her to cool back down again. Restarted her again with the same problem, plugged in the MSV and no fault codes present... going to try again in a weeks time and see if anything has popped back up again.

Anyone else got any ideas what else to check?

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can you borrow a known good maf as ive had this problem before. check the maf you have on your 4.0 is a genuine l/r item not a cheap aftermarket one which is just all black(no writing or stickers)on it.a new aftermarket one i purchased some years ago and fitted (same problem as yours)was useless and finally ended up in the bin,i fitted a second hand geuine maf and problem solved .might be worth a try cheap parts fail easily and tell lies when plugged in,also ive never known a fuel filter block up on a p38 petrol before if it did it would not run at all.

also check the little rubber pipe which fits on the fuel pressure reg at the rear of inlet manifold has not split or perrished