My AAR has low OHM reading.

[Paulporsche]

Have you checked all your ignition components--rotor, cap, plugs and wires?

Did this symptom just start, or was it after you did something to the car? Did that shop do any tuneup, timing or other work?

You mentioned the AAR being almost completely closed. Tony or someone else may have to tell us, but I THINK it is supposed to be fully open when cold and only 3/4 closed when warm, although I'M NOT COMPLETELY SURE ABOUT THIS. You may have try to manually reset it. I sprayed a little WD40 in mine to free it up. Best to do this w/ it removed as WD40 is flammable, or use a non flammable spray, carb cleaner may work, or at least let the spray drain out/dry.

Also make sure your timing is correct and the sensor plate in the mixture control unit is @ the correct height and moves freely.

[brianhiggi]

Paul, the car has had a surging idle since I bought the car 2 years ago, the car hadn't been started for quite a while prior to my buying it.
The car has NOT always been hard to start. It began being hard to start after I took it to a local car shop to have the timing, mixture, and idle adjusted. I also hooked up the air pump prior to taking it to the shop.
The cap, rotor, and plugs were replaced but I haven't replaced the wires. Would old wires cause difficulty starting but seem to work great when car is warm?

[Paulporsche]

It's possible. There could be condensation that dries up as the temps rise, or the connection between the wire and connector could be loose but tightens as things expand. Have you checked the resistance of the wires cold & hot? How old are thee wires? Do they show any signs of arcing? (You can see this in the dark).

You say the car hadn't been started for some time. How long? Have you changed the fuel filter? Did the PO use fuel stabilizer prior to putting it to rest?

Have you spoken to the shop who did the work that the engine now doesn't want to start when cold?

[brianhiggi]

The car had sat for a few years before I purchased it. I drained the tank and changed the fuel filter before starting it. I've only driven the car for about 500 miles since I bought it. Could the spark plugs be fouled in that short amount of driving time?
The car seems to run good when warm (aside from surging idle) does that mean that the spark plugs, fuel filter and and ignition wires are good?

[boyt911sc]

Originally Posted by brianhiggi

Thanks guys.
I've been avoiding doing the fuel pressure testing as I'm unexperienced but I think I just need to man-up and do it. I'll keep you posted.

Brian,

There is really nothing special or difficult about testing the fuel pressures. As a matter of fact, you could do a lot of CIS bench testing without running the engine just run the FP. Get hold of a set of fuel pressure gauge and people would help you do it in a breeze.

Overcome the anxiety. Let me know if I could help you get over this hump. PM me if you wish.

Tony

[timmy2]

Like Tony says, do the fuel pressure tests and set your baseline. Then you can look to things like mixture, false air and non functioning components. It's all guess work until you measure, test and prove the functionality of the system.
Basic troubleshooting 101.

[Paulporsche]

Could the spark plugs be fouled in that short amount of driving time?
The car seems to run good when warm (aside from surging idle) does that mean that the spark plugs, fuel filter and and ignition wires are good?[/QUOTE]

It probably means that these items are good. Unfortunately, the only way to know is by testing/looking. Your plugs most likely are perfectly fine, but they may be fouled from the too rich mixture or wet from continued unsuccessful attempts at starting.

You can verify this by pulling a plug and looking. You can also check the resistance of the plug wires w/ an ohmmeter.

As timmy and Tony have indicated, you need to establish a baseline for everything and CIS fuel pressures are a major part of it.

Bosch has always recommended, however, that all ignition items are verified as being in spec first before tackling the CIS components.

I don't know timmy but I can certainly vouch for Tony. He knows his stuff and can guide you through the testing.

[brianhiggi]

Thanks Paul, Timmy and Tony.
The more I learn, the more I know that Tony knows his stuff. I'll make him proud of me one day

[Paulporsche]

You know it's also possible your wires or plugs are just bad enough that they have a hard time getting a cold engine started, due to greater friction or whatever, while when warmed up they are able to get the job done.

Have you checked to see if your sensor plate is @ the correct height @ rest?
Have you checked the resistance of your wires? Have you checked the condition of the spark?
Have you had someone raise the sensor plate slightly while cold cranking to hear if the injectors are firing?
Have you checked that the cold start valve (injector) is working when cold, but not when warm running?

Just a few more things to look into...

[wjfk32]

Change your fuel pump relay--front hood--maybe bad contact-or not a consistent spark-etc..etc...

[brianhiggi]

Thanks for the good ideas.
Couple questions:
How would I check the cold start valve to make sure it's working when cold and not when hot? When I try to start the car when cold it starts for a second and then dies unless i give it lots of gas. Is that the CSV giving it the boost when I first turn the key?
I'll swap the fuel pump relay with the one in the engine compartment to see if that changes anything.

[boyt911sc]

Originally Posted by brianhiggi

Thanks for the good ideas.
Couple questions:
How would I check the cold start valve to make sure it's working when cold and not when hot? When I try to start the car when cold it starts for a second and then dies unless i give it lots of gas. Is that the CSV giving it the boost when I first turn the key?
I'll swap the fuel pump relay with the one in the engine compartment to see if that changes anything.

Brian,

The TTS (thermotime switch) is very robust and seldom go bad. This temperature switch operates @ 113°F/45°C (ON below/OFF above). So most of the time when starting cold the ambient temperature is below this temperature even if you live in a temperate state like AZ or in Death Valley.

There is no easy way to check the actual operation of the CSV. You need to physically inspect it and observe its operation unless you have the engine out. So with the engine in place, remove the two (2) securing allen bolts holding the CSV and watch out for the o-ring not to get lost during removal.

How to test the CSV:
1). Place the CSV in a plastic or glass jar to observe its operation during cranking of the starter.
2). Disable the ignition system by disconnecting either the CDI plug or the coil to prevent the engine from running momentarily.
3). Crank the starter and observe the glass jar. If you don't have a remote starter kit, have someone turn the ignition switch.

Presence of fuel in the jar would indicate fuel delivery. But you need mist like spray pattern during injection so observing it during operation is imperative. Another method you could use without using the starter is running the FP (engine off) and supply 12-volts to the CSV while the FP is running. Keep us posted.

Tony

[brianhiggi]

Thanks Tony for the easy to understand instructions.

I talked the the shop that did the work on the engine. They said that the mixture was adjusted to hot running specifications but that it's too lean to start the car. He also said he doesn't have the gauges to test the fuel pressures anymore.

The shop said they'd do a free smoke test to detect air leaks. But should I check the fuel pressures before I do a vacuum leak test?

[boyt911sc]

Originally Posted by brianhiggi

Thanks Tony for the easy to understand instructions.

I talked the the shop that did the work on the engine. They said that the mixture was adjusted to hot running specifications but that it's too lean to start the car. He also said he doesn't have the gauges to test the fuel pressures anymore.

The shop said they'd do a free smoke test to detect air leaks. But should I check the fuel pressures before I do a vacuum leak test?

Brian,

These are 2 different set of tests. It would be nice to know the fuel pressures before you bring the car to the shop since they don't have the gauges. But you have one and could lend it to the shop mechanic. Is the shop going to attempt to fix the problem?

If your fuel pressures are within spec, no significant source of air/vacuum leak, and has good spark and ignition timing that engine should start. I did not include gasoline because I use gasoline that is one year old and still could make these engines to run.

Tony

[brianhiggi]

I found another shop that can do the fuel pressure test and they have their own gauges. Should they be able to detect which systems are at fault with these fuel pressure test?