T25 Syncro startup issues driving me bonkers!

[Deadchemist]

Hi guy's!

I have a 1988 2.1 Syncro that I'm having a couple of issues with. Every now and again the engine will just not fire! It cranks fine but will not fire for love nor money. After I'll give up trying and leave it for 10 mins it will come back to life and then run fine until it is left overnight (but not always, i left it two weeks last month on vacation and it fired first time) I believe the problem gets worse when its colder but perhaps that's just my imagination, but it always seems to fire when its warm outside.
Recently its been juddering and running abit rough at low revs in 4th hear.

The strange thing is how intermittent the issue is. Went to start it today and it fired first time no problem. Yet over the last week ive been battling almost every morning to get it fired. I tried some starter fluid but that made no difference, also checked rotary arm, dizzy cap, coil, leads, spark plugs, injectors and everything seems ok! Next task today is to check the hall sender. Had anyone got any other ideas??

Many thanks

[Waldi]

Sounds bat - problems.
Alot of wires to check.

[Steve M.]

Have you checked the basics like cleaning every ground wire connection?
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[candyman]

Do you hear your fuel pump prime when you turn the key to the aux position? Get in the habit of listening for that first and see if perhaps you have a fuel pump issue, ie wiring, relay or pump itself. Then start going through your grounds etc...

[Deadchemist]

I'm just testing the hall sender atm. Can anyone tell me where the earths are located in the syncro bay?

Fuel pump is priming!

[markswagen]

Ground wires are on the cylinder head on cylinder 3 / 4 side, if you have AC under the compressor.
Follow down from under the coil, you will see them attach to the head.
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[Waldi]

Some of them at the engine
Some at the chassis in engine room
Some left from fuse box in the front

[MarkWard]

The time to check it is when it’s not starting. Assuming good even compression, it’s a fuel or ignition problem. Nothing wrong with cleaning grounds, but you need to determine if it’s a fuel or ignition problem. For fuel you need a pressure gauge and a noid light for checking injector pulse. For checking the ignition circuit you need a volt ohm meter. When I say ignition, I’m talking spark not the actual switch. A timing light is the easiest quickest way to check for spark.

Once you figure out what is missing then you begin to troubleshoot the cause. Good luck.
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[Deadchemist]

Thanks for the replies. I'll wait until it doesn't fire again and then go through the fuel and ignition. Ive cleaned the grounds and checked everything else i can think of so let's see how it goes.