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> Starting issues 2.0 FI
Fortyeights
post Jan 24 2017, 12:31 PM
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Hi,

Just bought a 2.0 FI, which has some starting issues?
Turns over fine but takes ages to pick up and fire, then sounds like it only running on two cylinders for about 30 seconds. But following getting it running and slightly warm runs nice.
What is the most likely culprit, I'm going to replace all the service parts, fuel pipes and injector seals as a matter of course, is the cold starting valve a likely culprit? I presume it gives extra fuel ?
If it is that, is it fixable or is it a replacement job ?

Regards

Carl
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brant
post Jan 24 2017, 03:38 PM
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really doubtful that it is the cold start valve
(unless the valve is stuck open and flooding the car)

the thermo switch for activating that valve only turns it "on" or causes it to add fuel at a very low temperature around 0 or 15degrees F.... something like that

so very unlikely your problem

but to rule out that it is not leaking and causing a rich condition, you can disconnect the fuel line to it and plug that line to see if it starts better. or pull the valve and make sure gas is not dripping out when it should not be

how are the plugs on the cylinders that are not working? rich or lean/dry?

really better to start with the basics and work through step by step
rarely does it solve anything to hunt/peck

that said...
the first things that come to my mind are:

-djet FI points in the bottom of the distributor
they run the injectors in pairs, so when one side of these points goes bad, 2 cylinders stop getting fuel at once. check the points, then pull the injectors and put them into cups... crank the motor for a second and watch the spray patterns for all 4 injectors to see if they are a good pattern and of equal amount

- common rich problems caused by the MPS diaphragm failing.. car barely runs or won't start at all
- another common rich problem can be caused by the CHT which if it fails will signal the ECU to run excessively rich and barely start or barely run.

still like stated above. You really need to go through the basics first when diagnosing fuel injection. Making sure that your valves are adjusted correctly, your timing is correct, and plugs/wires/cap/rotor/points are all working well before moving onto the FI components.

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BeatNavy
post Jan 24 2017, 04:37 PM
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Congrats on the new car.

If it's running rough when cold but better when warm I would tend to think more along the lines that you're running too lean -- not rich -- during warm up. I would also check your Auxiliary Air Regulator (AAR) to make sure it's open when cold. I also agree with Brant -- it's probably not the cold start valve -- unless you really do find evidence of rich condition.

If you haven't already, go here: http://members.rennlist.com/pbanders/djetparts.htm and bookmark it and read it repeatedly. Tons of good D-Jet info and troubleshooting tips. Troubleshooting D-Jet without really doing all the basics (tune-up, replacing vacuum lines, checking timing, valves, and fuel pressure, cleaning injectors, etc. etc.) can really be an exercise in chasing your tail, and it's really hard to point to the most likely culprit without more info.

What condition is the car in generally? Does it look like it's been neglected for some time, or has it been well-cared for? If the latter, then maybe it is something very specific. If the former, start a punch list of things to check/replace/adjust.
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Fortyeights
post Jan 24 2017, 05:21 PM
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Thanks for the help, planning to go through all the basic things first...just thought I'd ask the question. Cars well used but solid and pretty much original apart from an outer respray ......was being used in Cali up until last year.

Cheers

Carl
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pbanders
post Jan 24 2017, 10:46 PM
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Any time you get a "new" 914 you need to methodically go through each system on the car and do a full check-out, repairing and refurbishing as you go. Only after you've done this should you start going after specific problems. This applies to the whole car, not just the engine (i.e. suspension, body, brakes, electrical, etc.).

There are certain consumable parts that I would replace on any car, regardless of current condition. That would include fuel filter (possibly the fuel sock at the tank, too), fuel lines, air filter, injector seals, plugs, plug wires, cap, rotor, points and condenser (if not converted to electronic ignition), etc.

As for the engine, I'd check the charging system (connections/grounds, battery, alternator, voltage regulator), fuel system (supply, volume, pressure), ignition (timing/dwell, mech and vac advance/retard, spark), engine mechanical (compression, manifold vacuum, valve clearance), fuel injection system (see link in my sig).

This what my mechanic in CA used to do on virtually every car that came into his shop, regardless of what the owner told him was the problem. He told me that over 90% of the time, when he was done, whatever problem that existed was gone, and probably several other problems the owner hadn't noticed yet.

Good luck with your car, congrats.
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