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Engine no start, cranks, got spark, voltage at relay while cranking, terminal 87. I jumped both pumps they spin fine, fuel comes out of the rail through pressure regulator into container. This car has been sitting for quite a while but ran 6 months ago. Kinda stumped. Any ideas would be welcome. I have a spare parts car but I'm loath to shotgun parts without more information.
 

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Did you check fuse near relays under rear cargo shelf? Should be a 8 or 16A bullet fuse in a holder that the metal bar could be cracked. Are both the drive relay maybe a Bosch -125 and the tachimetric relay good?

I have forgotten more than I knew about Spider systems but hope this helps.

Does your Spider have the resettable rollover switch on firewall?

If you manually push open the flapper valve in air flow meter flapper does the fuel pumps run?
 

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Discussion Starter #3
Steve,
Thanks for the tips. I know nothing about the rollover switch. Where on the firewall is it? The fuse is good on the back shelf but someone put a twenty in there! I've tested the relays, they click nice and the voltage is there too. I know it's just something stupid I missed. I don't know these cars very well. This is my first Alfa. I'll keep playing with. The good part is I'm learning and in no hurry.
 

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The "roll over" or inertia switch for the fuel pumps should not exist on your '89. It went away some time in the mid-eighties. My '88 never had one.

The fuel pumps should run for a second when you first turn the key on and then run when the ignition switch is in the start position. After a starting attempt, is there evidence of fuel on the spark plugs?
 

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Did you check fuse near relays under rear cargo shelf? Should be a 8 or 16A bullet fuse in a holder that the metal bar could be cracked. Are both the drive relay maybe a Bosch -125 and the tachimetric relay good?
8 amp bullet type fuse is the original size/style. These fuses (and the fuse holder) are problematic. When they get old those fuses can look OK but somehow fail to allow electrons to flow. Replace the fuse holder with one that uses a blade type fuse to eliminate a known weak point.

Does your Spider have the resettable rollover switch on firewall?
It is not likely to have it. Alfa did away with the inertia switch around '85 ish. But they didn't change the wire harness - they just connected the two wires that would have gone to the inertia switch together and buried that connection inside the harness wrap. The switch on the earlier cars was located to the right of the hood latch. If everything else checks out but there is still no power to the fuel pumps I suggest you unwrap the harness cover in that area and search for a ?red/white? wire connected to a ?pink? wire. There have been a number of reports that this connection failed. Not very common but it can happen.

If you manually push open the flapper valve in air flow meter flapper does the fuel pumps run?
The L-jet Spider does not have the switch in the AFM to activate the fuel pumps.
 

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Jumping the big bosch fuel/drive relay socket between #30 & #87 should make the pumps work continuously.....try starting
If it starts like that your fuse/holder is OK, but your relay is likely bad.
 

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Engine no start, cranks, got spark, voltage at relay while cranking, terminal 87. I jumped both pumps they spin fine, fuel comes out of the rail through pressure regulator into container. This car has been sitting for quite a while but ran 6 months ago. Kinda stumped. Any ideas would be welcome. I have a spare parts car but I'm loath to shotgun parts without more information.

Doesn't this suggest he has fuel, just nothing coming out of the injectors. So either flywheel sensor not signalling the fuel injectors or maybe fuel pressure regulator (not enough pressure to actually fire the injectors)?
 

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yes Mike I agree... if he jumped the pumps and tried starting at the same time.
(I sort of read it that he just jumped the pumps to prove they worked..)

so if he jumped the pumps and it still won't start, then like you say my next check would be the FPR (take off the small vacuum hose and look for signs of fuel)...or clamp the return hose and try starting.
OP, farina, wrote: "fuel comes out of the rail through pressure regulator into container"...hopefully by this he didn't mean it came out of the vacuum hose on the FPR...

sensors: if either were defect would it spark? (he has spark)
 

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sensors: if either were defect would it spark? (he has spark)
Yes. Both are timing sensors... one is used to time spark and the other for fuel. So its possible the one for fuel has either died or possibly even came loose. Yup... happened to a friend of mine. The PO stripped the threads and one day while going through a coffee drive thru, the car died and he discovered the sensor was dangling under the car.
 

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Yes. Both are timing sensors... one is used to time spark and the other for fuel.
Correction, both sensors are for ignition - one for position (timing), one for speed (rpms). The fuel injectors are batch fired (all at the same time) not sequentially like the spark plugs.

In addition to checking for a loose sensor, check them for physical damage. I recall a no-start case. The sensors checked out OK with the ohm meter but when we removed them for a visual check one of them had a dent in the end. We replaced it with a used but known-good sensor and the engine started right up.
 

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Correction, both sensors are for ignition - one for position (timing), one for speed (rpms). The fuel injectors are batch fired (all at the same time) not sequentially like the spark plugs.
Interesting! Thanks for the clarification.
So if one or both flywheel sensors were dead and the ignition ECU didn't receive the necessary info for spark, the injectors would still spray?
 

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The drive relay needs to receive the expected 'tachymetric' signal to know that ignition is occuring. The drive relay then triggers the main relay and fuel injection occurs.* Thus no spark = no fuel injection.

*there is a bypass circuit during starting (when the key is turned to the 'start' position) that bypasses the drive relay to ensure that fuel is injected during starting. Then, once the engine starts and the key is released to the 'run' position, the drive relay is supposed to take over control of the fuel injection.
 

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Discussion Starter #14
Does anyone know what the fuel pressur should be? I jumped each pump individually and only ran the main pump into the container, it didn't spray like I thought it should. Would the fuel pressure regulator cause that and should I but some vacuum on the regulator?
 

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fuel pressure on Ljet is about 36psi, iirc.

pull the small vacuum hose off the plenum nipple that goes to the FPR (fuel pressure regulator) and suck thru it...does it hold vacuum?
 

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If the FPR passes the vacuum test, you can try starting the car with somebody pinching the return line varying degrees.
If you have any success, it confirms it could be bad.
Of course nothing beats splicing a fuel pressure gage into the cold start line.
 

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Discussion Starter #18 (Edited)
Ok , it started with a switch wired in to jump the main fuel pump. All sensors on the injection test within range. Compression on all for cylinders is between 140 to 150. It seems like number 3 and 4 are not firing. This engine has not run in years though. Tomorrow I'll check the spark in each cylinder. Weird! Won't idle and I have th sit in the car and play with the throttle, progress though. Any ideas? I am grateful for all the ideas so far, thanks to all who have replied. The engine was out of an 87 with a bad head gasket, I had most of it apart and replaced the gaskets, had the head milled and check at the local machine shop too. Progress though.

Number 2&3 cylinders are not firing.
 
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