BMW INPA - Anyone in/near Kidder with access to BMW INPA on my 1998 BMW Z3 2.8i E36

John Carmichael

John Carmichael

Regular Member
Joined
Jun 28, 2026
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13
Hi,

Vehicle is coming out of Covid storage, Problem is - It cranks but won't start without 2sec 'EasyStart' spray,
if/when it does start, it seems to run fine - BUT if it stalls (or I stop it) I'm back to square one!, ie no start on it's own!

I've been following online and OBD2 suggestions (ie Changed Cam/Crank sensors, EWS, FuelPump etc) but still won't start on its own!
 
Last edited:
Ianmc said:
Maybe it needs a good run following long term storage?
Click to expand...
Wish it was that simple, Currently No MOT, No Tax, No Insurance, Won't Start on it's own
When it has started I've had it running for over half/hour on the drive - didn't solve the problem
 
If it runs on EasyStart, it's fuel related. BTW, it's not a good idea to use EasyStart too much as it washes the bores, and the engine becomes addicted to it because there isn't enough compression to start on petrol.

Replace stale fuel. Confirm fuel pump is working. Confirm filter is not gunged up.
 
Pingu said:
If it runs on EasyStart, it's fuel related. BTW, it's not a good idea to use EasyStart too much as it washes the bores, and the engine becomes addicted to it because there isn't enough compression to start on petrol.

Replace stale fuel. Confirm fuel pump is working. Confirm filter is not gunged up.
Click to expand...
Tank drained & refilled, Fuel pump replaced, difficulty to imagine how filter could be stopping it when it runs after 'EasyStart'
 
John Carmichael said:
Tank drained & refilled, Fuel pump replaced, difficulty to imagine how filter could be stopping it when it runs after 'EasyStart'
Click to expand...
Fuel filter, not air filter.

EasyStart bypasses all the fuel side, and mixes directly with the air.

You may have blocked injectors, but it would be unlikely they were all blocked, so I'd expect it to attempt to run.
 
Pingu said:
Fuel filter, not air filter.

EasyStart bypasses all the fuel side, and mixes directly with the air.

You may have blocked injectors, but it would be unlikely they were all blocked, so I'd expect it to attempt to run.
Click to expand...
A 2sec spray of EasyStart gets it started, once started it seems to run fine, I left it running for near 1 hour the other day, BUT - once stopped, I'm back to square one, ie it won't start on its own - crazy car!!
 
Fuel filter is a good idea, or even just bypass it if you've got something to join it.

Road fuel doesn't store well at all, ethanol really doesn't do things like filters any good. It could easily be partially blocked
 
John Carmichael said:
A 2sec spray of EasyStart gets it started, once started it seems to run fine, I left it running for near 1 hour the other day, BUT - once stopped, I'm back to square one, ie it won't start on its own - crazy car!!
Click to expand...
Ahh, that's different, and makes a difference.

Several things are now confirmed as working that weren't before.

I now know that injectors are ok, fuel lines are clear, and that filter is also allowing flow.

Pre-starting, the system needs to build pressure. Is it doing that? If you can't hear the fuel pump prime, then it could be the fuel pressure valve. If the valve is permanently closed (unlikely, as they tend to fail "open"), the car wouldn't run after the EasyStart. If if is jammed open, the ECU senses the pressure can't be maintained, and stops the fuel pump after around ten seconds. A proper prime noise lasts for about 1 to 2 seconds, then a sudden stop. An open pressure valve pumps to about ten seconds , then the noise tails off.

To test the pump for priming, allow the car to sit for a while, and allow the pressure to drop. This can take a hour. Ignition to position 2 and listen to the pump. Bzzzzzz for 2 seconds and noise stops = good. Bzzzzz for about ten seconds and noise stops = bad.

Does it just run on idle, or can you rev it to 2500 and hold it there for ten seconds? This will show that it can handle high flow rates through the fuel system. Check for stuff coming out of the exhaust.

I'd put it on INPA, as you suggest, but without it, a compression test may show something, but you really need to see what the ECUs are telling you. The list of things it could be is almost endless, and you are chasing your tail without a code reader. I'm glad you have the sense to know this. My son would have bought a new cylinder head off eBay by now :) .

There are some generic scanners that work on 20-pin plugs. Hopefully, someone can advise you what they are, and their cost. They will be much cheaper than INPA, but not as good. They will tell you what's wrong, but probably only with a fault code. INPA gives actual numbers.
 
Pingu said:
Ahh, that's different, and makes a difference.

Several things are now confirmed as working that weren't before.

I now know that injectors are ok, fuel lines are clear, and that filter is also allowing flow.

Pre-starting, the system needs to build pressure. Is it doing that? If you can't hear the fuel pump prime, then it could be the fuel pressure valve. If the valve is permanently closed (unlikely, as they tend to fail "open"), the car wouldn't run after the EasyStart. If if is jammed open, the ECU senses the pressure can't be maintained, and stops the fuel pump after around ten seconds. A proper prime noise lasts for about 1 to 2 seconds, then a sudden stop. An open pressure valve pumps to about ten seconds , then the noise tails off.

To test the pump for priming, allow the car to sit for a while, and allow the pressure to drop. This can take a hour. Ignition to position 2 and listen to the pump. Bzzzzzz for 2 seconds and noise stops = good. Bzzzzz for about ten seconds and noise stops = bad.

Does it just run on idle, or can you rev it to 2500 and hold it there for ten seconds? This will show that it can handle high flow rates through the fuel system. Check for stuff coming out of the exhaust.

I'd put it on INPA, as you suggest, but without it, a compression test may show something, but you really need to see what the ECUs are telling you. The list of things it could be is almost endless, and you are chasing your tail without a code reader. I'm glad you have the sense to know this. My son would have bought a new cylinder head off eBay by now :) .

There are some generic scanners that work on 20-pin plugs. Hopefully, someone can advise you what they are, and their cost. They will be much cheaper than INPA, but not as good. They will tell you what's wrong, but probably only with a fault code. INPA gives actual numbers.
Click to expand...
Thank you for your thoughts Pingu
As Ive already stated - I've been following online and OBD2 suggestions (ie Changed Cam/Crank sensors, EWS, FuelPump etc) but still won't start on its own!
 
expanding on @Pingu 's post, maybe there is a problem with the fuel pump priming the rail, and holding pressure. There is a pressure test point on the front end of the fuel rail.
This video covers testing. For your engine you will need a right angle adaptor though, as the shrader valve is on the end of the rail, rather than the top.



EasyStart, replace that with one of those cheap spray bottles
https://www.screwfix.com/p/defenders-white-purple-sprayer-750ml
and put some petrol in it. It's what we used to prime the engine in my avatar photo, when it was being stubborn!
 
smiffy said:
expanding on @Pingu 's post, maybe there is a problem with the fuel pump priming the rail, and holding pressure. There is a pressure test point on the front end of the fuel rail.
This video covers testing. For your engine you will need a right angle adaptor though, as the shrader valve is on the end of the rail, rather than the top.



EasyStart, replace that with one of those cheap spray bottles
https://www.screwfix.com/p/defenders-white-purple-sprayer-750ml
and put some petrol in it. It's what we used to prime the engine in my avatar photo, when it was being stubborn!
Click to expand...
Thank you Smiffy, I'm looking into obtaining a pressure gauge
 
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