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So let me start off by saying I joined alfabb as a last resort because I've tried everything else I can think of and Ive already read everything I can find on google about alfa fuel injection including the hiperformancestore.com article.
My Spider has no fuel injection signal It will start and run off of what the cold start injector supplies to the engine then promptly dies a few seconds later no matter the throttle position, Ive already done almost all the testing I can do, tested the AFM, the flywheel sensors resistance/voltage,(at the connector under the hood and at the ignition ECU harness) the CTS, the TTS, the tachymetric signal from the coil to the fuel pump relay, replaced both relays behind passenger seat, tested fuel pressure, replaced fuel pressure regulator, checked/retightened all grounds I found in the manual, tested multiple injector harnesses with noid light,(nothing) checked ALL fuses, and tested voltage at 10.98v at the ignition and fuel ECUs while cranking. I thought I had it narrowed down to the fuel injection ECU because I was getting solid spark and no signal to the injectors. So I found a used one on eBay and ordered it. Put the new computer in and tried to crank with the noid light in the harness and I got a flash. So I plugged the harness back on the injector and tried to start it and all it does is crank, it wont even start off the cold start injector now. So I checked for spark with my timing light and theres nothing coming from the coil, so i replace the coil and same result, no spark. I think whats the last thing I changed before the spark died, .... new computer, unplugged it and my spark is back. So unless I am missing something I pretty sure I have two faulty fuel ECUs and I cannot find another used one on the internet. Any suggestions are welcomed and appreciated.

Thanks in advance,
Jake
 

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I tested resistance and voltage of both at the sensors leads and at the the computers harness, and they both checked out good, I also pulled them both out and cleaned them off.
 

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I might be really off and reaching, but have you checked the AFM, vacuum leaks, in tank fuel pump is working, fuel filter? ****, this is a tough one!!
 

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The AFM is working, I pulled the black cover off of it to check contacts and input/output voltage while cranking, no vacuum leaks, the in tank pump is new as well as both fuel filters, fuel pressure before the regulator is around 90psi and the FPR was replaced. Thats why I'm seriously scratching my head here. I find it strange that with the old ECU i get spark but no fuel and with the new ECU i get fuel but no spark. Which makes me wonder what kind connection the motronic comp has with the jetronic.
 

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I don't know very much about these cars but the air flow meter is the brain, make sure air isn't getting in/escaping through holes in the intake hose between the meter and the manifold. i had a similar problem.
 

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Was the ebay computer taken out of a running car?

ECU doctors can test the computers for a nominal fee (~ $75) and repair them if faulty for a larger fee (~ $300-$350 I think).

10.98V during cranking should be OK but might be marginal. Although Bosch never published a specific figure, emperical evidence indicates 10.5V is the approximate threshold for computer activation. Have you tried a jump start to make sure there is adequate system voltage? Clean & secure all connections in the battery to starter circuit to make sure all available electrons are usable. Also make sure all ground connections are clean & secure. Ground straps bolted to alumunim must be attached to 100% clean metal - a little corrosion acts as a insulator. The computer controls the fuel injectors by switching their ground connections - so make sure the computer's ground connections are good. These are black wires located at the right rear of the block and under a bolt for the Aux Air Valve.

Look inside all wire harness connectors. The metal connectors inside can get dislodged making it seem as though the connection is good when it is not.
 

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Jake03 - did you ever figure it out and get it fixed? If so, what was the cause and what did you do to fi it? My situation sounds like it is identical. I have replaced the relays, cleaned up the ground wires, replaced both the crank position and flywheel sensors, replaced all the vacuum hoses and sealed up any cracks on the intake rubber hose (from MAF to Plenum), have good fuel pressure and still my 86 veloce will start with fuel from the cold start injector and then die. I haven't had the fuel injector ECU checked out yet but at this point, I don't see much else it can be.
 

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I am very interested in this thread. I have a 1988 spider graduate and it will start and run for several miles and then acts like it runs out of gas even with a full tank. I let it sit and it starts and runs again for a while. Right now I am having lunch an a beer so that the car can sit long enough to get me home.
 

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I am very interested in this thread. I have a 1988 spider graduate and it will start and run for several miles and then acts like it runs out of gas even with a full tank. I let it sit and it starts and runs again for a while. Right now I am having lunch an a beer so that the car can sit long enough to get me home.
Clogged fuel filter?

pinched fuel line?
 

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Okay I think I am on the right track but still have some issues. I replaced the fuel pressure regulator and that seemed to help a lot. I also found that the new fuel pump in the tank had picked up some trash so I blew out that pump and replaced the fuel sock so it is running. The main pump is also running. I thought the car was running correctly and I took it out for a ride. It had a little over a 1/2 tank of fuel. The car ran well and then started to act up. It would run but then die if you gave it gas. I let it sit on the side of the road while I checked for pressure in the fuel tank. No vacuum there. I tapped the fuel regulator with the handle of a screw driver and I unpatched the Air filter box. Then the car started and I was able to head home. I stopped and topped off the tank and it got me home just fine. I am thinking that there could be trash in the fuel line even though I replaced both pumps and the filter and the regulator. What else can heat up or get a pressure of some kind and shut off the fuel supply? This is making my hair turn even grayer so any thoughts are appreciated!!
 

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I found a bad hose going to the fuel rail so I replaced that. This morning I started out to breakfast and it acted up again. Now when I replaced the hose I did not bleed the system so I guess that could be the issue but it started and ran okay as I drove out of the development. I am going to put a fuel pressure gage on the system to see if I can tell what it’s issue is. To recap, new pumps, new filter, new fuel line from tank to the main pump, new hose from the metal line to the fuel rail, new fuel pressure regulator. Car runs then looses power. It will idle but acts like it will die if you give it fuel.
 

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No need for any special fuel line bleeding. The main pump sends fuel at pressure to the FPR (Fuel Pressure Regulator). The FPR then sets the pressure on the fuel rail side and shunts any excess back to the tank. I've read that there are some fuel pumps that 'fit' but put out too much pressure - overwhelming the FPR. I forget the correct pressure the fuel pump is supposed to deliver - something like 40-60 psi. The incorrect fuel pumps put out around 100 psi.

A failed in-tank pump or faulty stepped hose (connects the in tank pump to the outlet pipe inside the tank) can cause problems that will be worse when the fuel level gets to about 1/2 full or less. A failed in tank pump will cause the main pump to struggle and a faulty stepped hose will allow the main pump to suck air when the fuel level drops.

Check inside the wire harness' plastic electrical connector at the Air Flow Meter. The metal contacts inside can get displaced and fail to make proper electrical connections.
 

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Thanks for the information. I think I found my issue. Someone has been into the fuel system and I have found and fixed several things that make me say that but the big thing was a missing fuel sock (filter) on the in tank pump. I replaced that pump and made the mistake of running it before the fuel sock got here. I hav since replaced that pump and added the fuel sock. I had also replaced the main pump so I thought it would be good. Wrong, it had picked up trash too. I just finished inspecting my original main pump and it seemed clean where I could see trash in the replacement I had tried. So I put the original pump back on and now the car runs. I also used a magnet in the tank to pick up as much rust and metal as I could. Now I know to pull the tank and replace it or at least have it cleaned and lined. Pay attention to the simple things first! That what I am relearning.?
 
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