1.6 Lack of Power/Slight Miss/Poor Starting

Right guys, here i go again, i apologise for all the questions so bare with me!

So my 81 GLi Cabriolet is finally on the road, history is: Its been laid up in a garage for 10 years, i then pulled it out and have had a hectic year getting it roadworthy, with lots of fuel related issues. Its on 90k.

What i have done:
-Fully serviced the engine, but i have not touched the injectors/fuel side under the bonnet, apart from a new air and fuel filter ofcourse.
-The fuel tank has rubbish in it, which i had problems with blocking the strainer in the end of the fuel pump, i have renewed the rubber fuel pipes at the tank, a new filler neck (the old being the cause of the rubbish, and i have extended the pipe from fuel tank to pump, so that it now includes a clear universal fuel filter. Me being an idiot i forget to clean the tank out when it was off the car!
-Second hand replacement fuel pump, off a late Mk1 GTi, so its Bosch rather than Pierberg (and a different shape). Same pressures though right?
-Brand new fuel pump relay and relay bypass kit.

The problems:
-It starts first turn, however runs very rough, and needs about 30 secs before it can be revved, almost sounds like its firing mainly on three, its not even!
I have disconnected the fifth injector, but then it won't start.
My dad says its running very lean on startup (by sniffing the exhaust!)

-When warm it idles fine, it also revs fine. But when theres load on the engine (accelerating or going up a hill). The engine feels like its labouring with any throttle, and feels rough (like its firing on three kind of). Unless with my foot to the floor, the roughness feels better, but theres no pull from the engine.
It kind of feels like anything above 2000rpm there is no power. Its certainly not right!

I was wondering if there is perhaps a semi blocked injector? To be honest the K-jetronic system is new to me, so i'm a a bit lost!

I was considering trying a bottle of 'injector cleaner' in the tank, unless its a waste of money?

Check and double check the timing marks for the cam belt and mark sure the rotor arm is pointing at the little line on the dissy casing.
If it's all ok try driving the car and advancing the timing till the car starts to "pink" under load the retard it a little till it stops, you will need a quiet road to do this as you have to keep stopping and adjusting the dissy the drive a little more.
If you have a timing light you could also have a go with that.

Once the timing is OK try and get your emissions looked at, try and pop to a friendly garage to see if they can do this for you so you then know if you have the right mixture, you can buy CO2 gauges to get a rought idea I bought a 2nd hand Gunson one for £35 from ebay and it's pretty near reading to what the garage was reading at my last MOT.

Found the version I have.
search "Gunson gastester" and there is loads.

http://www.ebay.co.uk/itm/Gunsons-Mark-2-Gas-Tester-/331654031074?hash=item4d381ee6e2

 

Thats a good suggestion, i did do the cambelt with a kit, and i checked the timing marks lined up a few times after turning the engine over by hand a few times, but i will check this.
I do have a basic timing light which i can use on it, which mark should i be using for this?

With the emissions, the MOT it had last week, it had an emissions test done and came with the printout (although i thought it was too old to need this?). My 91 Polo GT has never had emissions done in the five years i've owned it!
I asked the tester how it did, and he said really well, i will dig the sheet out! This would be when warm though (when it does run better).

the tester is probably used to testing cars that have lower co levels so might be running lean. should be 1.5-2%CO when fully warm

use the strobe light on the flywheel timing mark should be one at 6 degrees btdc I think it is the dot

 I would remove the filter you added and clean the tank out. does the pump sound ok?

 

1.6 is 0 degrees iirc, but not sure if thats with one or both of the vac lines disconnected? the haynes manual has the procedure well worth getting one. I remmeber I timed one like a 1.8 and it turned out to be wrong

rubjonny said

1.6 is 0 degrees iirc, but not sure if thats with one or both of the vac lines disconnected? the haynes manual has the procedure well worth getting one. I remmeber I timed one like a 1.8 and it turned out to be wrong

That would be ideal if it is, dug my timing light out tonight, its a very basic one with no settings, just a trigger…
I have a haynes and the Golf haynes restoration manual, some bedtime reading for tonight!

I had a look tonight, checked over the vac lines, all seem fine, but i've ordered new anyway.

This is the lump:


The little yellow cap, blocking a vacuum tube on the brake vacuum pipe section. Should this be blocked?
I've ordered some proper caps, as this almost looks like what comes in new brake parts where the pipes would go…

Next, all four of the injectors can physically be wobbled in their mounts, and moved around by hand (but not rotated). Surely not right!?

Anyone got an exploded diagram for how they mount?

Sport trucker, i don't like adding extra items from standard in a system like this filter, but it would run for 20 mins and cut out due to rubbish in the little strainer by the filter. I do need to clean the tank out, but the filter and pipe are high flow and the correct diameter.

even if you need to dial in advance its no problem with sbasic light on vw engines as VW thoughtfully mark the advance needed on the flywheel for you

dont think theres anything on the capped nipple in a 1.6 but ive not really worked on them!

the injectors on a 1.6 will wobble a bit as the hole is wider than the injector and the only way they secure is by the rubber seal at the top. if they move about very easy though its probably time the seals were replaced! dirt cheap from GSF so no worries there

If it idles fine and revs fine when warm the timing can't be that far out.

Could be all sorts if you've had muck in the tank. It sounds like fuel pressure at the injectors is wrong when cold which could be a numerous amount of things.

If the control pressure is wrong for whatever reason it'll never run properly. The control pressure is governed by the cold start valve located on the front of the block and alters the pressure applied to the needle in the metering head and which effects the ratio between a/f ratio when cold / warm. If main system pressure is down then control pressure won't be right. There are non return valves in metering block to govern main pressure.

Does it start from hot OK?

Thats good news, i will organise a set of injector seals anyway, can't be any harm in doing them! Do the injectors unscrew with their lines attached?

Edit: Like these?
http://www.ebay.co.uk/itm/VW-GOLF-MK1-SCIROCCO-1-6-GTI-EG-FUEL-INJECTOR-SLEEVE-INSERTS-063133555-x-4-A699-/191404805796?hash=item2c909d8ea4

I did time the car tonight, although i could not see a mark through the hole in the gearbox, just a clutch mounting bolt!? With all the pipes and wires etc in there it was hard to get the light shining down where i could see it though.
I used the timing mark on the crankshaft pulley, against an arrow on the cam belt cover, and set these to match. I hope these are right?
It was then idling at about 500rpm (according to the clocks) and didn't run smooth, so i changed the idle speed to around the 750rpm mark, much smoother. I only had chance to turn the car around at the end of my road, but it certainly seems better, smoother and when i put my foot down it actually pulled! Pulling away i gave it the normal amount of throttle and a tyre chirped, there still seems to be a slight miss, but a big improvement.
It has always popped a lot on over run, which thinking about it is timing being too retarded, right?

I will check the timing when its properly warm though, it had only been running for around 5mins, the temp needle is also leant back touching the back panel after one of last weeks jobs, so its jammed where the warning led is, so i can't see the engine temp, woopsYomp, is there a way of testing fuel pressure? It has a Bosch Mk1 GTi fuel pump fitted, which came off a latish cabby, whereas it had a Pierberg electric fuel pump originally. Would they run at the same pressure? How can the cold start valve be tested?
Also, it starts perfectly when warm!
 

Tick over should be at 950 rpm.

your ebay link is for the inserts that screw into the head, you need the injector seals they look like green doughnuts. the injectors just tug out, spray a bit of penetrating oil around the base to make them easier to remove. worth testing them all while theyre out!

the pierberg pump is probably a replacement, the originals were always bosch afaik. but yes if your bosch was from a mk1 gti then its fine, the metering head itself is what sets the actual pressure the pump just has to be man enough to cope with the demand

for the timing get a socket on your crank pulley and turn it to the mark lines up, then have a look down the flywheel hole. the TDC marker is pretty small so unless you put a dab of tipex on it tricky to spot when you;re trying to line it up! my digifant thread has some handy pics of the timing markers that you are looking for, obv ignore all the setup procedures:
http://www.vwgolfmk2.co.uk/forum/viewtopic.php?f=37&t=14915

my 16v thread has some pointers on the kjet system icludign testing the fuel injectors which still apply to you as well, ignore all the fancy 16v gubbins sections just look at the kjet basics:
http://www.vwgolfmk2.co.uk/forum/viewtopic.php?f=37&t=25972

only thing is the section on jumping the fuel relay doesnt apply as you have the ceramic fusebox the 18 relay doesnt fit. you dont want to use a switched relay either as this would mean the pump/wur/aav wiring isnt fused during the test, instead what you want is some 1.5mm2 wire with a fuse tapped inline, ans 2 male spades either end. push these into your fuel relay socket at the 30 and 87 terminal positions. you could put a switch in there too if you like so you can turn the pump on and off easier

duplicate post!

Right so, here i am again! Its scary i started this topic almost a year ago!

The golf is running much better, i managed to source the entire injection gubbins from under the bonnet from someone breaking a GLi local to me for a very reasonable price. It took 10 mins to fit the replacement warm up regulator (all i have changed so far) and its made a massive difference. The car has much more power, it doesn't cough, it starts first turn of the key and runs much more smoothly. Sounds very different too.

There is however one problem that has been getting worse that hasn't been solved. Basically when the engine has been up to running temperature or hot, it can be turned off and restarted perfectly within about 15 mins.
After that and the engine will turn over, start, run for about 1 sec and die. The engine then turns over fine but does not fire, it takes about 7-10 secs of continuous turning over of the engine for it to cough and splutter back it to life, it will run rough until revved and then runs perfectly.
However if the car has been left for a longer period after use and restarting, say 2 hours or more so the engine has properly cooled down, it starts perfectly.

I can't quite understand it? I'm looking at a PDF copy of the jetronic manual right now and i'm wondering if the 'thermo time switch' could be the culprit?
In my head it seems like its fuel evaporation? I only know of this on carb cars though!

sounds like you're loosing residual pressure, this will allow the fuel to evapourate in the lines causign poor hot/warm start.

this can be down to a fuel leak, faulty fuel accumulator, faulty non-return valve in the fuel pump or worn seals in the fuel pressure regulator in the front of the metering head

to styart with locate the accumulator and see if you can remove the small screw in the back of it, if fuel leaks here then the accumulator is dead.

Thanks for the reply rubjonny, that makes sense and what i was leaning towards!

In all honesty i have not checked any of this yet,  theres been a few jobs to sort for its MOT which had run out but as of Thursday its back on the road with a fresh ticket!

Fuel system wise i'm 99% sure it does not have a leak, i seem to spend a lot of time underneath it or under the bonnet recently so i'm sure i would smell this!
I will check the accumulator, googling how they work i imagine a split diaphragm would cause it to leak fuel where you say? I hope its not that though as they're not cheap!
It had this problem before and after i changed the pressure reg too so we can rule that out!
Fingers crossed its the non return valve, having a google i can't fine these available on their own?

I'm going camping with the Mrs the week after next and my plan is to take the Golf so i'll try and get further on this before hand!

yep if the diaphragm inside splits then this is what causes it, you can get them quite cheap now a fair few links have been posted about the place.

did you put new seals on the pressure reg before you swapped it? they're usually a bit squashed by now

the NR valve is available from classic parts, though the price has shot up recently
https://www.vwheritage.com/vw.cfm?act=vwclassicParts.search&classicSearchText=893906093

Nope, no new seals in the reg, didn't realise that was a thing! Could maybe save the old one that doesn't work then!

I will check the non return valve, i do have one spare on its original Pierberg pump, but iirc the actual fitting into the pump body was different on the Bosch item. I will check!

To confirm, the flat bladed screw right in the centre? Found 5 mins tonight to clean the paint off and have a crack but the only screw driver i had that fitted snapped off!  A job for tomorrow…

WP_002793 by Mathew Richardson, on Flickr

Get it soaking in Plus gas.

http://www.eurocarparts.com/ecp/p/car-accessories/car-maintenance-accessories/maintenance-fluids-and-greases/penetrating-fluids/?549774741&0&cc5_857

I had to order more plus gas but i got it soaked and cracked the screw out today, and petrol dribbled out!
I've taken a whim on the Ford XR3i item which seems the same, so one has been ordered and i will update how i get on with it, at worst its cheap enough to flog on and order a new part. Fingers crossed!