2.3-16v fuel pressure

ukhozi

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1987 2.3-16v, 2001 A170 (W168) Elegance TDi Auto, Eagle SS /VW kit, 1999 Suzuki AN400
I have finally given in and have to sell my beloved 2.3-16v Cosworth to pay the extortionate prices wanted to repair the automatic gearbox on my A170.:cry:
But I can’t as it runs rubbish! I still have the old problem of it being rubbish under 4,000 rpm.:mad:
I took it to a Boshe specialist in Malaga thinking they would put all the right instruments on it and come up with the fault but all they did was bypass number one pump and fit a new accumulator and filter which improved it for 3 days and then back to crap.
Putting diesel in it by mistake and then having to drain it out also improved it for three days, so something got lubed and improved its function.
I was wondering if it could be that the fuel pressure bypass unit between number one and two inlets could be faulty and allowing too much pressure in the distributor and thereby to the injectors, this would explain why she runs like a banshee from 4,500 up to 7,200 rpm and smooth as silk at a tick over of 2,000 but not low down and the exhaust and plugs are sooty.

Work so far;
The compression printout I was shown was 5.4 on all four but he did it with the throttle closed, as all four were the same this ruled out individual cylinder problems, it doesn’t use any oil anyway.
A check on the valve clearances showed clearances were all within tolerance and cam timing hadn’t jumped on the chain, (not that I can see how it could do it but it has been suggested). Cam shaft lobes are in perfect condition.
Plug leads are new silicon ones with new metal shrouded caps. New plugs, OK
I changed the complete air flap and distributor assembly with a known good one and it made no difference.
New air filter, no change.
Repaired and taped air pipes from rocker cover to air valve, no change.
Air valve opening and closing as it should on 12v command from relay.
Exhaust O.K.
Voltage protection relay OK.
Fuel relay changed and no difference.
All wiring check on temp sensors etc and any cracked, iffy areas taped up.
Comments please :confused:
 
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ukhozi

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1987 2.3-16v, 2001 A170 (W168) Elegance TDi Auto, Eagle SS /VW kit, 1999 Suzuki AN400
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Stripped down the air flap and distributor (ending in 010) yeasterday and found the plunger retainer that screws in the centre was loose and had infact almost dropped out, checked the original distributor (ending in 020) and found that the retainer was also on its way out, couldn't find any other faults so I may be onto a winner here. Anyone else had this problem?
Pete
 
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ukhozi

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Narrowed it down to a single problem and I'm sure someone will put their finger on it straight away.
I managed to get the car running fine, if in need of a bit of fine tuning but I switched it off and then it would only fire up and die.
On checking the starter injector, it opening under electrical command for a second, the engine starts and stops when the starter injector cuts out and there is no fuel at all in the injector lines.
Pressure a plenty in the lower chamber of the distributor, fuel pressure regulator, starter injector line, input to EHA, so pumps etc OK
NOTHING coming out of EHA to upper chamber, even with connector off, (reads 49 Ohms as it should).
Forget ignition system, works fine.
No O2 sensor, no Lamba, etc, basic 1987 model 2.3-16v.

So what is it that closed the EHA? I have three and all are the same, I have 2 distributors and flap units and two fuel pressure regulators, one from a 2.3-16v and one from a 2ltr (but it should still get the car running) swapped around until I am dizzy with no change.

Definitely nothing going through the EHA to the upper chamber is the problem, why?
 
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ukhozi

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1987 2.3-16v, 2001 A170 (W168) Elegance TDi Auto, Eagle SS /VW kit, 1999 Suzuki AN400
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Dry injectors 2.3-16v 1987

I still haven't solved the mystery of the dry injectors, removed all wiring from area of temp sensor and checked for resistance etc, check all plugs and socket in the regulator area. Changed the EHA again. Still starting and running for two seconds, still no fuel in the injector lines. At least I got the front windows and electric seat working ;)
 
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ukhozi

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1987 2.3-16v, 2001 A170 (W168) Elegance TDi Auto, Eagle SS /VW kit, 1999 Suzuki AN400
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Anyone out there, Any ideas, hallooooo,
Car running OK three days ago, switched off and now just start every time runs two seconds and cuts, injector lines dry. Can't see it being mechanical as machines work and continue to work untill they break and the K-tronic is 99% mechanical, nothing broken, so???
 

kth286

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E320 Coupe 95
Fuel pump relay not holding on, so perhaps it is an ignition switch fault you now have.
 
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ukhozi

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OK tried hot wiring the pumps for full time running (relay 30 & 87) and no change. Ignition switch checked and +15 and acc OK +15 holding when switch returns to position 2 from start position 3. Pressure at distributor lower chamber and starter injector, car starts. No pressure in upper chamber and injector lines, car will not run. ???
 
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television

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I have the full Auto data work book for your injection, if you want to know anything about any component and how to test please ask I only have it for 1984 to 1988 its Bosch KE
 
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ukhozi

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1987 2.3-16v, 2001 A170 (W168) Elegance TDi Auto, Eagle SS /VW kit, 1999 Suzuki AN400
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Thanks guys, just need to save up £200 for the test kit and I'm laughing. mind you if I had £200 I'd be laughing too.
Droping the fuel pump unit Monday to see if there is a problem there even though I am getting pressure up top, without all the expensive pressure guage kit I am having to do it by unit test, as in , if it is correctly assembled, not leaking and working then it should do it's job. I know the idea of two pumps is more to do with reliability than power but if one pump goes down would that drag pressure down as the fuel would have to get past the dead pump?
 
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television

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Fuel pumps

Just take a lead off one pump and the car should run, put it back and take the lead off the other one, and the car should run.
If the output from a pump is poor, take it off and emerge the pump end into a bowl of diesel and run it backwards, this will take out all on the crud,and it will be like new.

to run the fuel pump all the time either bridge pin 7 to 8 or take the relay out and short out pin30 to 87
 
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ukhozi

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1987 2.3-16v, 2001 A170 (W168) Elegance TDi Auto, Eagle SS /VW kit, 1999 Suzuki AN400
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One little item is when I accidentally (would one do it on purpose?:Oops:) filled it with diesel, it ran a lot better after draining and refilling with petrol for a couple days, would this throw any light on the problem?
 

television

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Diesel will dissolve sediment in a petrol fuel system, and this could well be what has caused the problem
 
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ukhozi

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Thanks Malcome, I'll rip it all out and sort it,
Peter
 
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ukhozi

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1987 2.3-16v, 2001 A170 (W168) Elegance TDi Auto, Eagle SS /VW kit, 1999 Suzuki AN400
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O.k. every thing removed, cleaned, tested and refitted, still the same, so pump pack out of the equation????? starts, dies dry injector lines.?????
DSC01248.jpg
 
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Number_Cruncher

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1995 W124 E300D TE
What happens if you disconnect the electro-hydraulic actuator? You should get basic limp home running of the engine - i.e., you should get fuel to the injectors.
 
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ukhozi

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Nothing happens if I disconect the EHA, I have tried diconnecting everything apart from the position sensor on the throttle body and still nothing.
 

Number_Cruncher

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So, if you bridge the fuel pump relay, and run them all the time, and you then move the air flap to mimic air flowing into the engine, can you hear the injectors beginning to spray? (If there's any doubt, pull one or two out, and watch them.
 
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ukhozi

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Nope, nothing comes out, I have even removed the pipes from distributor to injectors and blown them through, and replaced them of course, even checked the little filters in the bores the pipes fit into, all clean. There just isn't anything passing into the injector lines.
 

Number_Cruncher

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OK

With the fuel pumps running, is there any return flow of fuel to the tank. i.e., are the pumps producing enough pressure to overcome the primary pressure regulator?
 

television

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The pressure check should be done. Should be 5.5 bar in the main line, and 03-04 bar lower in the lower chamber when hot. the return rate of fuel should be 130-150cc per minute
 
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