Bad fuel pump relay or security system interference?
Thread Starter
Track Day
Joined: Apr 2003
Posts: 18
Likes: 0
From: Sacramento, CA
Bad fuel pump relay or security system interference?
With help from forum members (wally!!) i'm making progress. Fuel pump is good. I tried to swap relays to test for a bad pump relay. What is the secret for getting those little buggers out anyway? When i tryed to pull out the pump relay switch the cover came off. I probed it to see how i could then remove it and i heard the fuel kick in. when i held my finger against the right side of the relay (closing the contacts i guess) the car started and ran. I have been suspiciuos that my security system has been preventing my pump from running. How can i test for this? should i take out the relay (probably breaking it in the process because the cover came off) and replace or try to test security system??
Addict
Rennlist Member
Rennlist Member
Joined: Jan 2003
Posts: 20
Likes: 0
From: Sydney,Australia
If you have only the factory alarm then the fuel pump isn't directly routed through it, only the EZF controller. A circuit diagram here really helps, but you can disconnect the alarm at the connector NEXT to the central electrics board (DNK which side on an LHD, since mine is RHD!), however you must then bridge across pins 1-6 to get any power to the ignition and LH controller. My problem with the alarm system resulted in ignition failure but the ful pump continued, so when the engine was restarted, the raw fuel in the exhaust would cause backfire, so I don't think that the fuel pump was switched off. Note that this will only work for the earlier alarm modules, the S4 types are far more entwined in the electrics. Also, check in case someone has added an immobiliser; they may be trying to route all the fuel pump current (instead of relay coil current) through it and it may have failed, or the (often) dodgy wiring may have died....
Burning Brakes
Joined: May 2002
Posts: 1,208
Likes: 4
From: Las Vegas, Nevada
Weird,
I posted no less than three times on this exact topic over the last week.
Check for threads regarding a non-starting 1984 over the last 20 or so threads.
On the 84 I was working on, the alarm system was indeed the culprit. There is a connector Z on the fuse panel and you would need to bridge pins 4 and 6 on that connector to bypass the alarm system.
I have no idea if this applies to the 85/86 MY but I guess I would like to know since I own an 85 myself.
The alarm system on the 84 would prevent the AFC from engaging the fuel pump relay. Just like yours, if I manually engaged the fuel pump relay, it would run, however, spinning the starter motor would not engage the relay through the AFC like it is supposed to.
Try locking and unlocking both doors a few times to see if that helps.
If not, post back and I will see what I can dig up on the 85./86 cars
I posted no less than three times on this exact topic over the last week.
Check for threads regarding a non-starting 1984 over the last 20 or so threads.
On the 84 I was working on, the alarm system was indeed the culprit. There is a connector Z on the fuse panel and you would need to bridge pins 4 and 6 on that connector to bypass the alarm system.
I have no idea if this applies to the 85/86 MY but I guess I would like to know since I own an 85 myself.
The alarm system on the 84 would prevent the AFC from engaging the fuel pump relay. Just like yours, if I manually engaged the fuel pump relay, it would run, however, spinning the starter motor would not engage the relay through the AFC like it is supposed to.
Try locking and unlocking both doors a few times to see if that helps.
If not, post back and I will see what I can dig up on the 85./86 cars
