2.1DJ starting/running problems

[Boris89]

Hello

After many hours searching the forums and trying various things, I have decided to ask you all for some help.

I have a recently purchased 89syncro with 2.1DJ Digijet engine. The engine was not running very well from the start which has now develped into not starting. The issue manfested itself as a slight misfire at low revs high load (ran fine on open road), low power (my 1.9 DG has more power), odd erratic cranking on startup seems to crank slower and almost stop turning when its trying to fire. This has recently got worse to now not starting, sometimes cranks over fast with no signs of firing but when it starts to fire cranking speed slows right down to a very slow speed alsmost like its hydraulic. When starting from cold it seems to fire up and run fine on tickover for about 15 seconds then splutters and dies each time. When I can coax it along to warm up it seems to be on 3 cylinders unless you rev it, and pops and splutters especialy in the low rev range, but still cuts out eventually. I am suspecting fueling issues.

From the last garage bill I noticed that the injectors have been micro cleaned but have been installed with black sealer rather than the correct seals, resistance across the teminals if ok on all 4 injectors.
Odd black sealer holding air flow meter lid on?!
The fuel pump was replaced for a second hand unit (this can be heard to pressure up on the ignition key)
The ECU coolant sensor has been replaced.
Throttle body switch checked out ok on resistance.
Idle controll valve working.

Any help much appreciated. Rob

[eatcustard]

Welcome

Check that the earth strap is clean.
Have you changed your HT Leads?
Fuel Filter been changed?
Checked compression of cylinders?
Coil OK?


Others with better advice will be along

[Aidan]

Hi, welcome
where is you ?

[Boris89]

Thanks for getting back, I am in Perth Scotland, very cold and snowing to be out with a multimeter, brrrr.

Thanks for the tips, strangely enough I have just ordered some leads, plugs and fuel filter earlier today, seemed to be the next logical thing without busting the bank. Didnt check the strap oops will do tomorrow. Dont know about the coil I figured that as the van had been running if a little badly before I had not considered it.

The van has been hacked about a bit. It had an LPG conversion on which was part removed, bits blanked off and missing, I am sure thus may also play a part. I have spent sometime today repairing damager wires and connections which got it starting again but unfortantely not contiue running. Is there any easy way to comprssion test with out a gauge?

[wasserleaker]

if the airflow meter lid has been removed and stuck back on, its possible that someone has altered either the air flap spring pressure (notched plastic ring) or possibly moved the resistor wiper position from std, which alters the fuel/air mixture, or both! both can potentially screw up the running of the engine and cause popping on over run, or too much or too little fuel to air, setting up with a CO meter when the engine's up to temperature may be an idea. as a rough guide tho, you could check spark plug insulator nose colour after running at normal temp for a while, (if its not so running rough it won't run for that long!) to try and gauge if its running rich or weak

[Boris89]

Hi there, thanks for the info,. I have just changed the plugs but as the engine never got off the 'choke' the last time I got it going, they were all black or maybe this is how they always were? Three of the plugs were dry and sooty and one had a more satin appearance and stank of fuel, I am wondering if this is the cylinder which is causing the miss. I cant help wondering if one of the injectors is faulty or is recieving an intermittent signal or something or may be the cylinder is low on compression.

I am reluctant to pull the injectors out to test as they have been stuck in with sealer. Does anyone know where I can get replacement seals for them? I have found the fuel filter and this looks like it has been recently changed.

My next step once the weekend comes is to isolate the idle sbilization module (just to rule it out), clean earth strap, and see if the new plugs and leads make any difference. I will pop off the AFM lid and see if there has been any adjustments made. Can test it at the same time. If it decides to run for more than 15 seconds will get it warmed up and check plugs and try and get it set up in a garage.

Thanks.

[syncrosimon]

The seals you speak of were available from VW a while back, and were only pence each. After running for a short time, leave the engine for ten minutes. Then go and undo the very small screw on the metal petrol hose joiner on the rhs of the distributor. The result should be a healthy leak of petrol (only a small amount but take precautions) This will show if your injectors and regulator and fuel pump are holding the pressure. Should be pressure in there after 30 minutes or more, could be your rich cylinder has a faulty injector. A leaky injector is a typical cause of poor starting, especially when hot.

test your AFM easily like this.
http://www.youtube.com/user/syncrosimon ... Tn8dyzn9a4

The differing colour of the plugs will be down to poorly injector, bad spark, or poor compression on that cylinder.

More info on the AFM which is a generic model here
http://www.efinnegan.com/Porsche/MiscIn ... build.html

[wasserleaker]

an easy way to identify a duff injector is to remove the electrical connector block from each inj in turn, with the engine running..... if you pull off the connector and the engine runs worse, then there's a fair chance that one's ok. if you pull off the connector and it makes no difference to the engines running, it indicates that the inj isn't doing its share! this won't show up a fault in the wiring to each injector tho, and good earths (brown wires bolted to left cyl head as viewed from rear) are important to the injectors.

[Boris89]

Hello there,

The good news is that the engine is running again. New set of plugs and leads and disconnected the two plugs on idle controll unit and plugged them together. Just fixed a coolant leak and cleaned the earth strap. Cranking is still slow and laboured. maybe the pinion bearing? It still runs abit rough in the low rev range at low speeds with little power and a slight miss but this dissapears when the revs rise.

I will check the plugs after driving it around abit tomorrow and try your injector trick.

[mm289]

If you can, i would still do a compression check. Mine was running but sounded rough and turned out to have very low compression on no.4 10 minute job on these if you have a compression tester and well worth it.

Also, whilst the plugs are out does it turn over more easily - if not suggest starter motor needs some work!

Cheers,

[Boris89]

Will do, should be able to get a compression tester from a mate next week.

Thanks for all the help everybody. Will report progress next week.

[Boris89]

Ok, Compression test now complete and showing 7,7,9,1. Almost no compression in one cylinder and stranger still no blow out of the breathers and strange intermittent running as runs smoother at speed, so this is pointing towards valves right? Any ideas on what this might be, sticky/burnt valve, valve clerances too much? Just putting off the inevitable head off job. Will re do valve clearances just incase first............

[Aidan]

yep valve clearances need checking, I worked on a van last year that had no inlet opening at all on one cylinder and another barely opened the exhaust, yet it had supposedly been running fine till it ran out of fuel, on the way home after having just been bought

[Boris89]

Well, checked the valve clearances today and it didnt make any difference. I did struggle to get the exhausts rockers to rock when the adjuster screw was backed off, is it usual for them to be tight? There were signs of damage to the top of no 4 valve spring cap as if the adjuster had been backed off too far at some point, but I expect this would cause be the opposite problem to low compression.

Unfortunately on no 3 I did notice a lifter circlip that must have come adrift and was rattling around the end of the push rod. It looked bent so likely had not been installed correctly. I reckon its going to have to be a head off job.

Rob

[mm289]

Hiya,

likely you will eventually end up taking the heads off to look at valve wear and other problems but be aware that its a bit like pulling a thread on a wollen jumper, you keep pulling, and pulling, and pulling then realise you don't have a jumper left

When you pop the heads you run the risk of snapping an exhaust stud (easy to repair) or a head stud (difficult to repair). if you want to see whats involved etc look at my thread on rebuilding 2.1 WBX.

Before you start down that road just a couple of things to check.

1. Are all the adjuster nuts on the rockers screwed in around about the same distance? if not check:
a) that the push rod has settled in the hole in the middle of the lifter. When you do these in situ it can drop out and rest on the edge giving you a false reading - especially likely if you have backed off the rocker all the way (ask me how I know )
b) if you have one rocker adjusted in a lot further than the others it could be a sign that the lifter is knackered or not "pumping up"
2. Do a leak down test on the cyclinder. If you can invest in a leak down tester which you can get for about £60 and hook up to an air compressor (even smallish one will do). This pressurises the cylinder with about 90 psi and allows you to see how quickly the pressure drops. OK, so whats the big deal? Well, by doing it this way it is much easier to figure out where you are loosing compression, cause you will hear/feel it escaping from the valve seats and can tell inlet or exhaust, see the water bottle bubbling (liner seal) or feel/smell the oil vapours escaping from the sump (piston rings). Gives you a much better diagnostic and doesn't need the engine to be turned over.

I had no compression on No.4 (nearside closest to rear of van) and when I stripped the heads they look (so far) to be in really good nick. I now wish I had bothered to do the leakdown first before stripping cause I would have known exactly where too look.

Hope this helps, and if I am teaching granny to suck eggs etc, sorry

Cheers,

MM