1985 pininfarina quits after 3 to 5 minutes

[rieg1]

Any one on here ever had a car drive you crazy? I drove this car for years with out any problems, put it storage for 12 years got it out and running last year and it drove me crazy with it quitting every time just a few miles from my home, every time. I can let it sit for a few minutes 5 to 10 and it will start back up and run mostly fine the rest of the day with just a few hesitations at untimely places like intersections. If I start it in my barn and let it run it will run for 3 to 5 minutes and quit same thing it does on the road. It will not start back up unless it sits for a few minutes. I put a new pick-up coil in it, no difference I had the module checked, it was fine, new wires just because. I also replaced the fuel tank with a new one and replaced the fuel filter. Now here is the catch if I take the fuel cap off it will not quit but still has the hesitation at maybe ten or twenty minutes apart. Sounds to me like something with the emissions system any help would be much appreciated before I completely loose it. It is currently sitting on four jack stands awaiting me to something to fix it. thanks in advance for any suggestions. rieg swoh

[RRoller123]

Charcoal canister clogged. The only way that makeup air for the gas tank gets to the tank is through that metered charcoal canister top opening, then out through the cloth covered hose on the bottom, and back to the tank.

[davery]

Charcoal canister clogged. The only way that makeup air for the gas tank gets to the tank is through that metered charcoal canister top opening, then out through the cloth covered hose on the bottom, and back to the tank.

Could he just disconnect the canister to see if that solves the issue?

[MattVAS]

Yes that is a clogged vent system. The clog can be anywhere in that venting line. Remove/replace those lines. Clean them out all that good stuff. And that is all easy to do.

The hesitation you're still getting could just be that it still tired from sitting for all those years. Your injectors are probably still spraying poorly and other little issues. Also which coil did you use in your replacement?

[RRoller123]

+1. Alternatively, you could temporarily put on a vented gas cap and see if it runs right, if so, then it confirms the venting problem.

Make sure item 4 on the drawing, the 2-way valve, is not clogged. Guaranteed that it is, with grey paste gunk, due to age. Clean it out, and it should require some pressure to open it IN BOTH DIRECTIONS. It is found along the line directly above the rear axle, driver's side.

[rieg1]

Thanks guys I think we are on the same page. I cleaned and replaced some of those lines and removed and checked that two way valve tonight I think it was ok I could blow air through it. I will start it tomorrow and see what I've got keeping my fingers crossed. I'll let you guys know. Thanks again! rieg

[herfiat]

Consider your ECU. I had a hot start problem for over a year (you can see my post from 18 months ago), then, 6 mos ago = no start, then, start and stop, then start and run beautifully, then start and run like a diesel dump truck. I replaced EVERYTHING TWICE - modules, pumps, fuel lines ...well, I have in guts in my 1985 Fiat.
Desperate women do desperate things - I went to the Brits (who best know about awful running sports cars!!??) I found www.atpelectronics.co.uk - holy smoke - Steve and Paul at ATP were terrific! Within 14 days (shipping time included) these guys diagnosed my ECU, rebuild it, and shipped it back DHL for $262.00US - OH! plus my one way shipping to them of $48US What can I tell you = she runs like a champ!!!! All this time its was the ECU - There is a guy in Germany who sells used, not rebuilt 0280-000222 for $700 plus shipping on Ebay...... So, my $300 rebuild was a bargain....we won't tell the husband what I spent on all the aforementioned new guts.......
It may not solve your problem - but, it did mine.
I write this because when I joined this forum and wrote about my hot start problem, I got great support. Time to pay it forward! Jacqui

[rieg1]

I wish I could report that my problems are solved but no so much. I am a grain farmer so I have been planting 15 hours a day, not much time to work on my car. I have checked all the lines involved with the emission system, replaced some blew out the others all lines are open. I can blow air through the charcoal filter so I am guessing it is not blocked, however I am going to create a bypass around it. I just finished planting and now its raining so I am going to give it a shot tomorrow, we shall see. Thanks again for the suggestions all ideas are welcome. I will sure report my progress to all. Thanks again; rieg swoh

[Odoyle]

There is a vacuum check valve above the rear axle, which is most likely clogged and should be replaced.

[RRoller123]

That is item 4 on the drawing below. I think he already checked that.

[rieg1]

All vacuum lines are open and two way valve is clear not sure witch direction it is to be installed but I have tried it both same result, quits in three to five minutes. I can feel the vacuum with my finger where the line connects to the engine, that hole is needle size had to use a mirror to see it so I got a needle to see if it was open and it is. I am now stumped and thinking it might be the ECU as suggested by (herfiat). My brother sold his 85 recently or I could have switched it out to check that. Where do I go from here? In the mean time I am rebuilding a tractor to get ready for hay season. Thanks again, throw something else at me I'll try anything. rieg swoh

[tima01864]

Do you need o depressurize the fuel to look at that Two Way Valve?

[lglade]

The two-way valve is in the vapor collection system, so there should be no fuel in it. The pressure it sees during use is also very small. So there's no need to depressurize that line before disassembly.

[RRoller123]

+1

[scheerd]

When I bought my Pinny (84), I noticed when I got home (damn!) that the fuel cap had a hole drilled in it, and the fuel tank was imploded (sucked in). There was also a solid plug cap on the charcoal filter, which is a no-no, as it needs to vent vacuum. After failing smog, I got a new fuel cap, and like yours it wouldn't run for more than a few minutes, and loosening the fuel cap showed negative pressure.

I don't know exactly what was wrong, as the fuel and pressure return system is weirdly complicated, but I replaced everything (3-way and 2-way valve, charcoal canister and cap, fuel cap, fuel tank) and reviewed every fuel line for proper routing just to make sure. I assume that when the last owner replaced the flex lines, they got things crossed. IMO the culprit was the 3-way valve (orange on the left side of the trunk space), and if I remember right, it seemed that the 2-way valve (#4 in the diagram) was reversed.

All is good now. It's very hard to ID which return lines go where, as they run parallel, but it's possible to track it down. Just be super rigorous, and it should work out. The valves are pretty cheap, and the charcoal canister is also only $38, so mostly elbow grease and head-scratching, as you have the diagrams from another answer posted here.