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2001 A170 CDi. '87 BMW 320i. '95 Eagle SS Kit car, '99 Suzuki AN400X
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177 Posts
Discussion Starter · #1 · (Edited)
I have had problems with my 1897 2.3-16v starting and a lack of power under 4,000rpm for ages, I took it into a so called Bosch specialist who looped #1 pump out of circuit so I had reduced pressure at the distributor, so lack of power all over, not just under 4,000 but it went back to crap in 3 days anyway.
I replaced the pump as well as connecting it all up as per book as I thought having it running dry for a time could have damaged it as the idiot didn’t disconnect power as well.
Last year I filled with diesel by mistake and had to flush and re-fill but the car ran well, (still not 100% though) for 3 days until dropping back.

I replaced the complete air flap and distributor assembly from a ’86 2.3-16v that was a runner, no change. So instead of mucking about in the street I kicked my dead A170 out and got her into the garage downstairs and pulled the thing apart;
I have been all over the engine and I cannot see any mechanical problems, anyway it runs really well, when it does run.
No problems with the fuel distributor all clean and set as should be.
Both pumps working OK, full pressure, new accumulator and filter.
No problems with ignition or timing, (fixed anyway) new plugs and leads/caps, great blue spark so we can forget ignition, anyway it runs from 4,000 up to 7,200 rpm smooth as silk.
Valve timing and clearances all OK
No problems with lamba, oxygen sensor or resistor on #4 inlet as it doesn't have any, (pre-’88 German model)
Voltage overload relay OK.
Fuel pump relay OK, Ignition on, pumps prime, pumps cut out, pumps run with engine..
ECU OK
Pipes to starter air valve/injectors removed, checked and repaired/sealed where dodgy, all OK now.
Fuel return line is clear
BUT, it floods like hell when I switch on and the pumps run to the point where there is a spray of fuel out of the plug holes when I take the plugs out and crank the motor and a puddle of fuel in the chamber under the throttle body. As soon as I dry it out it starts but floods straight away.
There is pressure in the injector lines and the pipe from distributor to fuel pressure regulator (FPR) but nothing in the return line from the FPR?
The vacuum pipe on the FPR is sound but I sealed it where it joins just in case.
I disconnected the return pipe and the pipe from the distributor to the FPR and connected the return pipe to the regulator outlet. The car started straight away and ran for a couple of seconds, I can only assume this is due to fuel in the distributor, inlet tract and cylinders getting burnt.
To my mind it seems the FPR is not opening to balance the fuel pressure at the 5.8 bar needed (I don’t have the money to buy a set of pressure gauges) and there is there too much pressure in the injectors so they just spray fuel in like crazy. There is also a screeching noise when it's all connected but not when I take the FPR out of line.
Just to check, after standing all night in the garage I removed the pump relay and the car fired up for a second, removed all 4 plugs and they were dry, replaced the pump relay and turned on the ignition, the screech was back, failed to fire and when I removed the plugs all 4 were soaked.
 

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Registered
2001 A170 CDi. '87 BMW 320i. '95 Eagle SS Kit car, '99 Suzuki AN400X
Joined
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177 Posts
Discussion Starter · #3 ·
Nope.
There is residual pressure in the line from the distributor to the valve so it must be closed or it would leak out. There is also residual pressure in the injector lines so it's not those either anyway it would require all 4 to leak at the same time.
 

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Registered
2001 A170 CDi. '87 BMW 320i. '95 Eagle SS Kit car, '99 Suzuki AN400X
Joined
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177 Posts
Discussion Starter · #4 ·
Found it,
Cracked ceramic disc in the distributor differential valve on number 4 and a split O ring on the injector slits.
Now all I need do is get fuel to the injectors as with the replacement distributor the injector lines are dry. but the starter injector is OK and fire up the engine. ho hm.
 

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Registered
2001 A170 CDi. '87 BMW 320i. '95 Eagle SS Kit car, '99 Suzuki AN400X
Joined
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177 Posts
Discussion Starter · #6 ·
Good job I have three then. :)
I am running (or tryiing to) a 0438 101 002 but I have a good 0438 161 001 and a duff 0438 161 028 (this is the original one with the cracked disc) I cannot see any difference in them, anyway they should all be OK to get the engine running and ticking over, the dam annoying thing is two days ago it was running fine on the set up I have in now and now without being touched it's back to starting but not running and dry injectors again. Grrrrr
Good news, I go the drivers seat electrics sorted when checking out the aux fuse box.
 
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