Fiat 2000, remove FI?

[Adammaltese]

Hi, I’m a new member of the forum.. new 81 Fiat 2000 owner and have a questions I haven’t seen specifically answered. I am thinking of pulling off the stock FI system and replacing it with a Weber 32/36dfev and 1800 manifold as well as a mechanical fuel pump and want to hear if I am making a poor choice.
My reasoning is this… I am an OK mechanic… just OK. I have always done my own work on all my cars and seem to fair reasonably well. The bane of my existence has traditionally been FI system troubleshooting. I have a list of vehicles that I have (mis)-diagnosed over the years.. from multiple Volkswagens to various Volvos and now a Fiat too. The process usually involves pouring through manuals and repeatedly arriving at the wrong part… replacing it ($$$) and finding out that it’s not the culprit until finally I accidently stumble across the issue…. Sometimes weeks later.
This Fiat is a new thing for my wife and I… a third car! So in theory it really doesn’t need to be reliable. Except in practice it really does. Example. We don’t have kids for a whole evening and have a drive planned to our favorite lobster shack… drop off the kids… race home top down, jump in the Fiat… No Go. (a whole lotta missing and running really rich… I am tracking it down… think the fuel pressure is too high… beside the point). Anyway I am realizing that I want a car, really, that is fun to drive, Simple to work on beside the road (with a saintly patient wife looking on from the grass beside the highway), and can be trouble-shot quickly and MacGyvered with a piece of old foil and a Leatherman.
Am I a fool to think that a weber carb is that answer? I have been fooled by this before (one VW camper and a 80’s Rabbit) and have replaced FI systems with Carb systems (the Rabbit was a carb I had from another car) and had less than stellar performance results. I would love to hear some thoughts from better mechanics than myself on this issue before I take of a perfectly good FI system and replace it with a system not originally intended for the car. Also note that I live in Maine and though we constantly complain about breathing the whole countries exhaust we have no qualms about producing it ourselves (no smog laws.)… go figure.
My specific mechanical concerns are this:
Does the setup really get simpler as a carb system (seems like a no brainer… but)? Does the car as a whole become less forgiving of a carb system vs a FI system? (FI systems are robust and long lived and don’t require a whole lota maintenance etc.)
Everyone is talking linkages… is the carb linkage a PITA to find and set up?
Will my plan of a super-simple single gas line from the existing gas tank through a filter to a new mechanical fuel pump work? Will it draw from the existing line at the top of the tank OK? Does the pump (correct sized) mount up OK on the 2000 block (where the ERG pump/valve thing is now right?)? I wouldn’t need a return line or any type of pressure relief valve right (two less complications)? Am I crazy to do this work to have a less cluttered car? I realize that all of this “complication” was originally engineered to improve performance… am I “throwing out the baby with the bath-water?”
Lastly, am I doing a disservice to the future owners of this car by ditching the FI system (it is no museum piece… but still)?
Any thoughts would be appreciated!
Thanks
A-

[bradartigue]

Absolutely not. Comparing the Bosch FI system to a carburetor is literally a comparison between modern technology and 1930's technology. L-Jetronic is very easy to work on, and, since FIAT was a very cheap company to begin with, the way L-Jet was installed is a bare minimum application, it has only a few sensors and switches in the engine compartment. No altitude compensators, knock sensors, APCs, or any other of that stuff.

L-Jetronic, once properly sorted out, is going to be far more reliable, far more efficient, and deliver more power than any bolt-on carburetor setup you can find. Unless you want to do some serious engine work (and it doesn't sound like you do), L-jet is going to give you the most bang for the buck.

If you lived near here I'd let you drive two identical Spiders with the exception that one is a CS2 (carbureted) and one is a CS0 (fuel injected). The CS2 has a single weber downdraft on an 1800 manifold. I don't care who you are, the seat of the pants comparison always go to the FI car, it is faster, has more torque, doesn't ever smell like gas, starts perfectly every day, and gets significantly better gas mileage.

Learn about your L-Jet system, there are plenty of resources online, get it sorted out, and enjoy it.

[narfire]

I really like my car with the FI. I have added some engine mods that have made a difference and love the car more now.
I'd be keeping the car as an FI and just perhaps when funds permit, get another fiat with a carb.. Why not have two?

[beater]

I have a 1977 fiat obviously with a carb. It has been changed to the 34 DMSA with the mechanical secondarys and bigger bore. I have gone with the smaller chrome breather and a header and I have to tell you I really like the look when compared with the fuel injected model. It is a classic car and has a classic look under the hood. Don't know if goes as fast but it's plenty fast enough for me !

[divace73]

Keep and Fix the FI, as Brad stats, a properly working L-Jet system is spot on. If you want the reliable get in the car, turn the key without pumping the accelerator then the FI is the go.
Don't get me wrong I do love carbs, especially the twin variety, but they do require more tuning / adjusting.
Just to give you an idea, the wires to my cold start valve broke off, I was thinking since I am in Australia it really isn't that cold here so I'll keep them disconnected. It makes a massive difference on starting. When they were connected it would start first go, without it I have to kick it over a couple of time.

[vandor]

That sure would be a lot of work to get worse mileage and less smoothness...
With the help of this forum you will be able to fix whatever it needs.

[JConnerly]

I agree with the above. I bought my 81 one year ago and all but one of the drivability issues have related to timing, valves, or ignition problems. The only issue I had with the FI was solved by following the advice I got from the experts on this forum. I love my car just the way it is. Starts easy, gets good mileage and runs strong.

[RRoller123]

Really good smooth low-end torque with the FI too. I can accelerate from 2000 rpms in 4th on flat pavement no problem with no downshift. Nice and smooth, no lugging.

[2ndwind]

I had a fair amount of trouble when I first got my car. It turned out to be a combination of things; bad starter, Ignition switch failing, poor grounds, and a bad air flow meter(AFM). I paid $500 for a "professionally rebuilt" one. Later, for another FI 124, I got a used one that worked perfectly for $70! What cleared up a lot of my problems was replacing my air flow hose ($39.95 new) that had a couple of cracks in it allowing unmetered air into the system. Now it starts every time and runs nicely.

[Kevin1]

Keep the FI. There are a number of things to check before you go digging in to the point of replacing parts. As far as roadside repairs go the FI is one thing you would likely never have to deal while on a drive. Once it is all sorted out it should be pretty much trouble free. The FI on our '80 has been pretty much bulletproof for ten+ years since buying the car.
Over the years I have found that most "fuel system" problems are actually ignition problems that have been misdiagnosed. Next up is correcting repairs made by previous owners with items like paper clips and band-aids.
The L-Jet system is very straightforward and should not bee too hard to sort out. This is the best time of year for convertibles in Maine.

[Adammaltese]

Thanks for all the above comments... the FI's have it.

And thank the forum for the huge amount of solid information

I have found a surprising amount of stuff out there... I have Bradley Artigue's Maintenance and Mod's doc and a photocopied version of the Fiat FI shop manual. They are quite helpful (especially Artiques) and pawing through the forum has been a great help.

I run a new diagnostic when ever i have a few minutes...

Currently know: Car not running great for previous owner; sat for (4) years, ran (poorly) on old bad gas (yikes!), we bought drained gas (actually didn't look as bad as I thought it might, not full of rust anyway), Ran decently on new gas with injector cleaner added for about 1.5 hours of total run time... them progressively ran worse, really rich.. fouled plugs, finally stopped running. Humpf...
Poked around... Fuel pump on all the time. Found wires at "double relay" jumped to bypass relay and force pump on all the time. pump off, car runs great (for 5 seconds at a time), checked Mass Air Sensor... someone had previously opened it and F-d it all up, bent contacts, stripped set screw and worn through rheostat (from use). set that all to rights... no change... now cracking open "Double relay" as pump will not run when Mass air flap opened (mass air points are now operating correctly) and have no shorts in wires to relay. Still wondering if the fuel regulator is over pressurizing system as an additional complication but getting to the bottom of the fuel pump controls issue first.

Ironically had almost the same exact scenario play out on an old 79 volvo Dl (stick!) that had been parked for 10 years then fixed up slick and sold at auction to a friend. Spent better part of a very cold winter trouble shooting only to find that the auction dude had jumped the fuel pump on under the fuse panel. (My theory is) The pump on had forced the engine to run (poorly) on the bad gas... but when replaced with clean new (full octane) gas... the new gas slowly cleaned up the inside of the system until the constantly running pump would drown the engine (wouldn't even start and plugs dripping w/ gas after a 2 second crank). We found the jumper pulled it off... the pump began correctly cycling and the car ran great (still does). This was after checking almost every component.

The real issue is not seeming to be the FI system but the layers of "repairs" put into motion because of a previous issue.

All that said... handling aside... a clean-stripped down block and no wires in site still has some appeal... but with the overwhelming views of this experienced Forum... The I think the FI will stay for now.

Thank you all!

will let you know what the offending component is when found...
A-

[Adammaltese]

Ok… so got it….

The symptoms:

Running really rich… (fouling plugs within 10 min of running) intermittently stalling and not restarting… (engine would just catch for a half a second and stall).

The cure(s):

Blown fuse to the fuel pump (one of the ones conveniently hidden in a tangle of wires under the dash)… this apparently stumped some previous mechanic… he opened up the air sensor and bent the fuel pump contacts back (looked like an open bobby-pin) and messed with the rheostat screw/position… slopped a bunch of black goo on the plastic cover and glued the whole jumble back together and then (in frustration?) wired the fuel pump “on” at the double relay.
This was only half of it… the temp sensor was giving intermittent readings (resistance) from the connector at the control module (resistance was way too much for the parameters given in the manuals or nonexistent depending on how hot the engine was) not sure if this ended up being a wiring/connector issue or a sensor issue but replaced them both… cleaned up all the ground locations I could find… and eureka! Runs like a top (however a tops run!)!

What I think was happening:
The control module was getting high resistance readings from the temp sensor (high resistance equals cold engine… REALLY cold engine). The module then provided a really rich mixture thinking the cold block needed it when in fact the engine was hot… all that extra gas fouled the plugs. When the wires/sensor got nice and warm the resistance jumped to “1” or an open circuit and then the system shut down (start-stall syndrome). Sound right?

Anyway… runs great now. Now on to the other issues… breaks, rust, etc….

Thank you all for the advice and previous postings, links and online guides. You made the fix possible!
Adam

[vandor]

See, we told you it was simple

As usual most of the problem is because some crazy mechanic worked on it...

[dantye]

….

Anyway… runs great now. Now on to the other issues… breaks, rust, etc….

Thank you all for the advice and previous postings, links and online guides. You made the fix possible!
Adam

Ditto the support for FI over a carb conversion. Just one pointer as you work on it: Always SEARCH first on this forum before posting questions. If you try 2 or 3 different wordings of your question/issue, you will usually find it has already been asked and answered here - frequently with pictures and step by step instructions!

Good Luck!

[2ndwind]

Hooray, Another smooth-running spider due to persistence and the help of this forum after initial frustrations