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Matty-H

KR 16v feeling rather flat and gutless

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Just wanting to pick your brains.

 

I've recently purchased a 1.8 16v and all is well apart from it feeling very under powered and sluggish low down. Its also absolutely rubbish on fuel.

 

 

All the engine timing is bang on as I replaced the cam belt at the weekend thinking it may have been a tooth out etc. Turns out it was not and was and is still all correct. Its so flat under load especially at low rpm and only seems to pull after 6k.

 

Anyway I was having the odd look around and found the distributor was fully advanced and it felt even worse when corrected to 6deg standard timing. Shortly after I found ''K-STAR'' hiding under the scuttle tray, all intact and plugged in..

 

I know the purpose of these piggyback ecu's were mainly to stop pinking when running on less than 98 octane fuels, and that they work in 500rpm increments adjusting the ignition timing to suit/overriding the standard ecu. And that they work with the ignition timing being fully advanced.

 

I then tried it without the K-STAR, Set the timing to standard and it was even worse than before!

 

Any ideas? My friends 1986 1.8 8v Mk2 golf puts me to shame and pulls/feels a lot better than my KR and leaves me standing..

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If the vacumn hoses look tired, then they probably never have been changed since new, so I would change all of them first. As its not a big job nor expensive.

 

From there try changing the fuel filter as it could be starving the fueling system.

It could be a fuel pump. There is a lift pump in the tank, and there is also the inline pump.

 

If you are changing the one in the tank and need the car the same day, I would suggest getting another sender unit for the tank , change the pump on it then fit it to the car on another day. Changing the lift pump requires time. As the connection from the fueling system to the pump is an awkward connection.

 

Also there are tests to check various other components like fuel pressure, WUR. These can be found by using the search on this forum.

 

On the KR the fuel mixture can be adjusted but, I would refrain from adjusting it unless you know what your doing.

 

Another would be if the KR injectors are the original then they will be far past there prime, this not a cheap option.

 

the KR is a bit fiddly to get right, if all else fails take it either to a garage who knows what there doing or to someone who has the knowledge.

 

Good luck!

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I am fairly familiar with the k jet system but never really spent a lot of time working on them. I am a mechanic by trade, had a lot of mk2's and completed many engine conversions, rebuilt engines and all the rest.

 

It riddles my head with worms when seeing all the pipes/vacuum lines on K-Jets lol! I'm more used to the Digifant side of life from previous experience with ABF's and later 8v's.

 

The things I've already checked are the vacuum lines and all fairly obvious things like the inlet pipes/metering head/plugs etc. I've changed the whole sender unit/lift pump a few days ago as the gauge was not reading correct and the lift pump was a bit worse for wear. All that side is working fine and the main pump sounds sweet with no nasty whines or buzzing.

 

I'm led to believe from what you have said and other posts on here and elsewhere it could be down to a fuelling issue..

 

I can feel it being a long journey with the old lump and I am pondering a better upgrade without going over the top

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The 1.8 goes perfectly well when set up right, even on the heavier-than-mk2 corrado shell, something is amiss for sure.

If the cam belt pulley marks all line up and the flywheel mark tallies, and when running it idles at around 6 degrees advance (bin the kstar for now) then I'd consider checking the inter-cam marks, these little 'o' marks should point at each other at tdc, perhasp the chain was changed and these were never set right.

I'm assuming it has the correct plugs and they are in good nick, cap, rotor etc.

Ideally a system pressure check would be done, including the control pressure from/to the warm up regulator, at least check the metering head flap moves smoothly. You could also do an injector spray test visually, and measuring delivery into bottles, jumping the fuel pump relay connections on the fuseboard and using the battery connection to make/break power to the pump, open the airbox and wedge the metering flap open a little to simulate air flow. then check spray patterns are noce cones and delivery over 1 minute is even between injectors.

I'd also set the base timing advance to 7 or 8 personally, if mit doesn't pink under hard load at low revs, I've run 1.8 and 2L lumps like this fine on regular unleaded.

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I'm hoping to get some time on her this weekend David. Trouble is now It's burning oil like a tank too.. I will still have a go at getting her to run better still. Also the idle is being odd too, I've tried resetting it a few times and it seems to be fine for a while and then starts to raise slowly over a day or so to around 1100rpm regardless of the engine being at normal operating temp or cold.. correct procedure followed when I have done it.

 

WUR is ringing a bell for me, Am I right to suspect this?

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Had the similar happen to mine a while back and it took weeks and different mechanics to figure out but it was the same as what Wullie' mentioned.

Turned out some previous DIYer changing the timing belt didn't go down the right path and had the crank pulley off but didn't put it back on tight enough or something and it wore the crankshaft key down on the inside. Timing and everything looked spot but it just wouldn't pull at all when it should have been spinning its wheels off. should be fairly straight forward to check once the pulley is off to see the inside of it if like mine the remains of the key are smeared about the place or missing.

goodluck!

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Righty I've done away with the K-STAR and I've set the idle and ignition timing again, runs better if anything, power is consistent through the rev range and the exhaust note is a lot more deeper opposed to before with the K-star and the ignition timing being fully advanced. Does not smell as rich any more and the burn smells pretty clean. Also changed the plugs as the oldies were not up to much either.

 

Also the oil temperature used to read over 110 - 118 at some points during driving and now stays around 96/98 degrees.

 

I'm looking into vacuum pipes again and noticed there is one that comes off the bottom of the 5th injector housing and goes to the crank case breather pipe, then off that and along to the air box. Surely that's not going to help? Picking up air from the inlet before the metering head I'd have thought it may make it run lean? or is it just another daft place for it to pull in crank case gasses and ''recycle'' them?

 

Also there is a vacuum pipe blocked on the bottom of the inlet manifold just above the alternator. I really could use some diagrams so I can be sure to get to the bottom of everything.

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