Hi all I recently acquired a corrado with a starting issue. So far I have got to the point where I think I have an electrical issue in the fuelling system. I have good spark but no fuel getting to the measuring unit. I'm a bit stuck as I don't know if what i am seeing at the pumps is right or wrong. Trouble shooting so far - Intermittent voltage supply on ignition to the in tank pump. Sometimes works, sometimes does not. I have only ever seen 10v here but think I should have been seeing 12v? Fuel pump works on an external 12v hobby battery. The accumulator and pump under the floor sees no voltage at all on ignition- is this right? Fuel was in the lines and the in tank pump will pump fuel on an external battery. No fuel makes it past the accumulator and pump under the floor in this scenario (tried with ignition on and off) - does it have to have voltage to pump or should fuel dribble through? When cranking relay 167 (replaced) clicks once and the measuring unit clicks alot. Fuse 18 for the pump is good. I dont know how to test for voltage at the fuse to check if it is 10 or 12v - can anyone let me know how to do this with the multi? The fuel pipe feeding the measuring unit is dry of fuel but the feed back to the fuel filter does dribble a little on cranking. When I replaced relay 167 there was a black wire stuffee into the relay. No idea what it is for but the chap i got the car from said the immobiliser had been bypassed because of a start issue. Maybe that is the dodgy by pass. I have tried starting and voltage checking with and without that wire connected. When I look at the wiring for the alarm system it doesnt look professional anymore - twisted wires bare and cut wires going no where. There are also a couple of OEM connectors not connected. I'll post a picture of the the mess. Before I delete the alarm system wiring - quite a job for a novice like me but I will trace and undo wires one by one - i wanted to check what voltage should be seen at both pumps when on ignition - is it 12v? Any other tests I should do before I jump into deleting the alarm system? Oh and any guidance on the best technique to re-join wires would be appreciated- I plan to twist, solder and shrink wrap. Thanks Matt
first thing fit a 17, 18 or 100 relay in slot 12, then the fuel pumps will be powered up with ignition. makes life much easier when troubleshooting the pump wiring, you should then see decent battery voltage at both pumps ignition on, the under car pump plugs into a white 2 pin plug near the lifter pump check voltage here as well as underneath. looking at the state of your wiring I think the immobiliser needs removed regardless, with the ignition and stalk wiring you can unplug that separately and replace with a fresh loom nicked out of a mk3 golf. the ignition loom same regardless but the stalk loom on the high spec/gti differs for the cars with dual chamber headlights so look for a poverty spec
Also whats a 17.1.8? Just trying to source things over the next week as the car isn't stored at home and I'm here for a week! Good timing on your reply as just rang around the auto electricians in Pembrokeshire but they refuse to look at it.
sorry that should have been 17, 18 or 100 you will have one for the x-contact on the fusebox you can pinch for your testing. it stops the wipers, blowers and rear screen plus a couple other things from working but nothing the car needs to run
Cheers! I will get out there now. Sent some feelers out for a mk3 loom to my breaker friends on facebook (or Corrado 2.0 16v loom) - if anyone reading has one please msg me. Cheers Matt
So plugged relay 18 from location 4 into location 12. I see 10v at the intank pump (think this should be 12) but doesn't operate. I see 0.2 volts at the underbody pump. There is a wire that the outer protection is cut. How do in find out where all these unplugged stock connectors are supposed to live?
This is the cut outer on the underbody pump. I have tested for continuity between break and connector and all good for now.
ok so do you have 10v at the under car pump plug now? white/blue connector is speed signal, might be unused or could be for spoiler module. grey/blue is dash lighting, again might be unused if there is just the one on its own. black/red is possibly brake lights on feed spare, used for cruise install. see where it comes from (if w/4, thats what it is) red wire looks liek a wire off the cluster loom for something, possibly brake pad warning for higher spec models, again see where it goes. the green single plug is possibly an ignition live for something, depending on wire colour ce2 looms are modular so sections can be split off separately same as the stalk/ignition looms, the cluster loom and headlight switch come out on their own as well plus brake light switch so can pull all of these out to give you a bit more room to work with whats left
Thanks, I'm getting there now. Pulled out the alarm. The wire to the fuel pumps had been cut off behind the relay board and hard wired to relay 167. Fixing that as i type now. Will check out those wire colours you mention against those unplugged connectors.
Right all wired back up. I see 12v at the underbody pump on cranking but nothing when on 2nd ignition. I still see 10v at the intank pump but it seems to need 12v to make a noise. Hmm
A two steps forward and 1 step back sort of day. Jobs for tomorrow seem to be re testing voltage leaving the fuse box and looking for problems on the fuel loom. I've bought a second hand loom plus ignition loom but managed to repair mine. I'm guessing there is resistance on my loom causing the voltage drop. The fuse is also getting hot.
its possible the fusebox itself is to blame, on my mk2 the main pump started cutting out randomly and I found the fuel pump fuse socket was totally melted due to corrosion build up inside from previous water damage. into the bin and a mk3 fusebox fitted all was well again
Cheers John and got your email i sent on the no reply in error! Electrics are now good - 12.5v at the relay, on the back of the fuse box on a spliced wire I could test and both pumps read 12.5v. Fuel is being pumped from the intank but it isnt getting throught the underbody pump. I've taken it off the car and applied 12.5v to it from a separate battery and it makes a very quiet noise but no signs of fuel comes out, admittedly most of it drained under the car on taking it off. I'm researching how I service this assmebly and look for blockages, but please let me know if you know!
take the non-return valve out of the end of the pump (the threaded but piep goes on) I've had these fail and stop pump getting through. also could try jumping pump backwards, sometimes can free out debris inside. but its probably just knackered from being sat. mk2 8v & 16v k-jet pump is the same, the corrado housing is specific though. pump is 191906091H, I'd replace the 3 screws that hold it in as well these rot, expand and split the casing. check the casing over very carefully though before you spend any money
Thanks John. Got the pump all disassembled and the pump is seized. Tried quite a few things to get it free - gentle taps with hammer and pulsating 12+v through it from a the external battery. It wants to go but is stuck. I've secumbed and bought a new one from Euro Car Parts as I want to get this car going whilst I am at the inlaws - 260 miles away from my house. £179 wasn't expected but saved loads on labour and the car cost me nothing because of these issues (88k on it and no rust to speak of so worth the effort to save).
Yay - we are up and running. Thanks John your help was invaluable in getting me to here. I ended up buying a new Bosch motor from ECP (pricey) as the old one was seized solid - tried lots of things to free it including pusling 12v through it. The electrics are behaving them selves now and I see 12.5v on both pumps with the relay bridged. I took the time to tidy up all the wires, ensured splices were covered and then I used that fabric type tape to wrap the wires up tidy. I had a casulty in the fuel line going from accumulator to filter (the smaller lengthed one - believe to be PN 535 201 218 A - the black plastic shrink to fit pipe split. I have used some similar ish clear pipe my father in law has for his tractors to get it running but it seems to leak. Do you know where I could get a replacement for my car - i saw some goodridge hoses for the KR engine for 85 quid but would prefer a cheaper option! The other thing I am really struggling with is remounting the underbody pump unit to the car. I've bent the metal clips that locate around the rubbers to a 90 degree angle thinking I'd bend them back into place once pump assembly is mounted but struggling to get the clips bent over the thread and bolt on top. Is there a better way!? And lastly my fuel and coolant gauge doesn't work. I dont know if they ever work or if it's something I disconnected when sorting wires out. I did see the fuel gauge reading more than full whilst messing about getting the pumps to work. Do you know which colour wires relate in the fuse box area, if any at all? The rest of the dash and electrics (spoiler, lights etc) are working well. Here's a couple of vids of the car. Thanks again for your help!
This is all I can find ( I only need the shorter one) https://www.ebay.co.uk/itm/Fuel-Lin...noa=1&pg=2047675&_trksid=p2047675.c100623.m-1 Are there any other options
Take the line to a local hydraulics place, they'll make you a new one easy as pie. The trick with fuel pump clips is fit them to the pump bracket first, then shove it on the studs. The design is ingenuous, they hold the pump in place for you while you get the nuts threaded For gauges check G1/5 is earthed, it's a brown/white wire off to the side of the head
