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83 1.9DG T25 engine idle issues.

Posted: 16 Feb 2025, 16:53
by Swordfish93
I am trying g to get my T25 (83 1.9DG) up and running but when I turn it over it will run perfect for about a minute then cut out. It will always start right back up again but will then cut out about 10 seconds later. I have replaced the pull down choke replaced vacuum lines and took the carb out cleaned it and put it back in and i am still having this issue please help

Re: 83 1.9DG T25 engine idle issues.

Posted: 16 Feb 2025, 18:17
by maxstu
I take it there is plenty of clean new fuel in the tank?
Have you checked fuel delivery volume?

Also condition offilter by petrol tank. Age of petrol tank; is it rusty. Perished fuel lines. Cone filter where fuel supply enters carb.

Try increasing idle by about 100 rpm to about 950-1000 and see if it still cuts out.

Re: 83 1.9DG T25 engine idle issues.

Posted: 16 Feb 2025, 23:16
by 300CE
As well as Stu’s suggestion, was there any build up to this beforehand or has it just started.

Also what carb have you got - it could possibly be the idle control solenoid or maybe a failing hall sender (try giving the lead on the side of the dizzy a wobble).

Just work through each element methodically and turn over each time to see if it makes any difference.

Re: 83 1.9DG T25 engine idle issues.

Posted: 16 Feb 2025, 23:19
by Swordfish93
How could the hall sender effect it if it is working fine on startup? I say this because I just replaced it as the old one melted in small engine fire by the last owner

Re: 83 1.9DG T25 engine idle issues.

Posted: 17 Feb 2025, 13:11
by maxstu
Perhaps a few good quality photos of engine bay might help with our suggestions.

Re: 83 1.9DG T25 engine idle issues.

Posted: 17 Feb 2025, 23:22
by 300CE
A failing hall sender can work intermittently so sometimes it will start fine and other times it won’t, but if you’ve recently changed it, i doibt this is the issue. Do you have a spare dizzy at all, it might be worth swapping it over just to see if it makes any difference.

Worth putting up some pics as suggested.

Re: 83 1.9DG T25 engine idle issues.

Posted: 18 Feb 2025, 09:29
by tobydog
Ignition amp?

Re: 83 1.9DG T25 engine idle issues.

Posted: 19 Feb 2025, 20:06
by Swordfish93
Image

I just bought this T25 and am the 9th owner. The previous owners did some strange things and I had to replace alot of parts to get it here.

Re: 83 1.9DG T25 engine idle issues.

Posted: 19 Feb 2025, 21:00
by maxstu
Aha! The dreaded fuel filter in engine bay. Get rid of it. There is already a filter by fuel tank and another in the carb. It doesn't need yet another one. That poor little fuel pump pushrod is pulling it heart to get fuel to the carb.

And while your at it, unless you are certain of the age and condition of the fuel hoses, replace with Colhine 100% ethanol pipes.

Supply from tank. There is a return, too. But out of stock.

https://brickwerks.co.uk/product/fuel-l ... l-dg-feed/

Re: 83 1.9DG T25 engine idle issues.

Posted: 19 Feb 2025, 21:54
by Oldiebut goodie
After that - it looks someone has bought a job lot of those terrible plastic shrouded terminals. Horrible things, the number that I find on Webasto wiring that are so poor that one little tug and the wire pulls out of the crimp. I immediately cut them all off and do them properly. Cures a lot of faults - whoever dreamt them up should be shot!

Image

Re: 83 1.9DG T25 engine idle issues.

Posted: 20 Feb 2025, 14:04
by Swordfish93
Thank you for the replies I will update if I can get it running properly. There was also an engine fire and the pull down choke and hall sender were melted plastic. I have replaced both as well as all vacuum hoses and fuels lines after the engine fuel filter.

Re: 83 1.9DG T25 engine idle issues.

Posted: 20 Feb 2025, 14:38
by 300CE
Thanks for the pic.  The things i'd be checking are as follows:

Idle control solenoid (red lead coming from the carb) that should click when the ignition is switched on

Ignition Amp as suggested by Tobydog - yours looks like the original and wouldn't hurt to replace just as a preventative measure and just check the connection

Fuel Pump pushrod - it looks like you may have the original fuel pump which maybe ok, but the pushrod might be worn.

Check the connections to the brake servo hose and ensure that its nice and tight

Vacuum hose from dizzy to carb - that looks original and i might look at changing that with a new piece of hose so it's nice and tight at both ends

Check and clean the connections to the coil - i'd be looking at replacing it as it looks quite old, but that's just me

Have the plugs and rotor been changed recently?  If not, i'd be looking at changing those as well.

Fuel filter by the petrol tank - if this hasn't been changed i'd look at a new one of those.

Let us know how you get on.

Re: 83 1.9DG T25 engine idle issues.

Posted: 20 Feb 2025, 16:20
by Stesaw
Where are you based? perhaps someones local to you to give a hand?

Re: 83 1.9DG T25 engine idle issues.

Posted: 08 Mar 2025, 10:36
by Swordfish93
I am based in Suffolk (Bury St Edmunds area). I just replaced all fuel lines and it did not fix the issue. I am gonna buy a new ignition coil and fuel pump rod next.

Re: 83 1.9DG T25 engine idle issues.

Posted: 08 Mar 2025, 12:04
by Che
Try the ignition switch, that's the issue I had with my 1.9DG WBX.

If looking for a garage,. try Weld Wagon near Diss.

Andrew and Val are brilliant.