Alfa Romeo Forums banner

1 - 17 of 17 Posts

·
Registered
Joined
·
416 Posts
Discussion Starter #1
I recently bought this 87 spider and just got it on the road today for the first time and I have to give it full throttle to get anywhere and it is running real rich. I removed the cat because it was compromised and believe that this is a long going issue with the car, Car starts up and idles fine. What has been replaced. New fuel filter and both fuel pumps, used AFM, all 4 injectors 3 new and 1 good used, distributor cap, rotor, spark plugs and wires. Also, removed and cleaned out fuel tank. Installed new o2 sensor. What was done in the past new cold start device, fuel regulator. Pulled new spark plugs after a mile run and looks like #2 is getting black compared to the other 3. I have checked and replaced 1 air hose in the engine bay, Car idles well and revs just fine under no load and engine sounds healthy. It takes a long time to get anywhere with the throttle to the floor and I can smell richness out of the exhaust pretty bad. Any insight would be appricated.
 

·
Registered
Joined
·
416 Posts
Discussion Starter #3
Both pumps and fuel filter are brand new with 0 miles on them. I believe that it had the same issue with old pump as well.
 

·
Registered
Joined
·
81 Posts
Cold start valve not closing or a Mass Airflow Sensor fault can cause rich conditions. Try cleaning the MAS 1st including the contacts as the cheapest and easiest solution.
 

·
Registered
Joined
·
1,041 Posts
Disconnect the cold start injector (quick and easy). If that doesn't help, install a fuel pressure gauge and check for proper pressure. Then check for proper fuel pressure regulator operation. I have also found that (for the most part) the Air Flow Meters (AFM) tend to become rich over time. I have had positive results tightening the clock spring (remove black plastic cover to gain access) a notch or two or three, which leans the mixture. I believe that the spring becomes weak over time and allows the vane to swing too far open. Before adjusting spring, use a paint pen to mark initial position.
 

·
Registered
Joined
·
416 Posts
Discussion Starter #7
If I had a blocked return line would this cause my issue of too high of pressure? I did not order a bosch pump but got something similar and you may well be correct that it is putting out too much pressure. The original air flow meter was messed with and the barn door flap would not close all the way is why I replaced it. If I want to adjust the spring do I go clockwise or counter clockwise? I may try to put the failed bosch pump back in and see if I can get it to run and see if it helps my rich condition. Never buy a car sight unseen. I would never have bought this car had I looked at it and drove it. The owner was a lady that had inherited the car and did not represent the car correctly as it was.
 

·
Registered
Joined
·
416 Posts
Discussion Starter #8
The fuel pump that I bought I just looked it up and it is for the alfa spider series so it is the correct pump. I have an extra fuel computer and I may try to swap this out among other things.
 

·
Registered
Joined
·
416 Posts
Discussion Starter #9
I replaced the o2 sensor with a generic one and what will the car do if I unplug the sensor? Will it go into a rich loop mode?
 

·
Registered
Joined
·
416 Posts
Discussion Starter #10
Also, all my sensors other than the cold start valve are original and wanted to know what would a fualty ecu temp sensor do?
 

·
Administrator
Joined
·
17,713 Posts
Without a valid signal from the O2 sensor it will go open loop which is slightly rich. Same with a faulty temp sensor. Neither should cause it to run very rich.

Check fuel pressure. A blocked fuel return line would cause excessive fuel pressure.

Click on the link in my signature for a page of DIY diagnostic info for the Bosch L-jetronic system in our cars (you may need to use the down arrow to open the full signature block).
 

·
Registered
Joined
·
416 Posts
Discussion Starter #12
Turns out I had an injector that was stuck open causing extra fuel going to #2 cylinder. Replaced injector and car runs well now. Going to have to check my oil to see if there is fuel in it yet.
 

·
Registered
Joined
·
1,041 Posts
How did you find that this was the problem? Fuel pressure gauge?
 

·
Registered
Joined
·
416 Posts
Discussion Starter #14
I pulled the spark plugs and could smell gas in #2 and the plug was soaked. The car had had a complete tune up right before I bought it and they also replaced 2 injectors out of 4. The fuel pump went out on me right after I had the car shipped home so I replaced the pump and filter after I pulled and cleaned the gas tank. The car sat for who knows how long with the previous owners. I am going to replace the last fuel injector next after I know that the line is clean.
 

·
Registered
Joined
·
1,041 Posts
I see this more and more these days. People try to start engines in cars that have been sitting for years before they insure a clean fuel supply. Contaminated fuel, pumped through the system, can wreak havoc on so many parts. Hopefully you have removed any and all components that come in contact with fuel, and have inspected and cleaned and tested and them, as best as possible. GLWYP.
 

·
Registered
Joined
·
416 Posts
Discussion Starter #17
I am hoping that I don't have to replace my fuel tank. I cleaned it the best that I could after I removed it from the car. I have a receipt from the lady that owned the car before me and she paid $900 to have he tank removed and fuel system cleaned including injectors in 2019 and it is only 2020. Time will tell.
 
1 - 17 of 17 Posts
Top