engine seems to not run right, where to start? Options

[914 RZ-1]

I've edited in bold red.

This is bit long, but I've numbered everything, so just answer the number(s) you want/can.

My 1.7L with a Pertronix (everything else is stock) does not seem to run as well as I think it should. Seems to be missing/runs a little rough. It will hesitate and surge just a little, not accelerate smoothly, when I press the gas. This is less of a problem when it is warm.

Lately it's been hard to start. It would crank and want to catch, but took awhile. Today, it just wouldn't start, even though it cranked just fine.

I'm thinking I need to check:

1. Fuel injectors. I've replaced 2, may need to replace the other 2. They all work just fine. Used a 9v mattery and some wires t osee if they "clicked".

2. Coil: the one on there looks like the original. Do these wear out? I've seen posts on how to test them, but I've seen conflicting numbers for results: + to - 0.75-0.81 Ohms, 3 Ohms, and + to distributor output 8-12 Ohms and 10,000-11,000 Ohms. Big difference! Replaced with a Bosch Blue. I checked the voltage on the old one from terminal 15 to ground and got 10.7V

3. Distributor cap: How do I tell if this is worn out? Replaced. I did keep the old one, though.

4. Rotor: How do I tell if this is worn out? Replaced. I did keep the old one, though.

5.Wires and Plugs: mine could be old, but how do I tell if these are worn out? Replaced. I did keep the old ones, though. On the plugs, they were WR7CP with a 0.023-0.025 gap. I replaced them with WR7CC+ with a 0.028 gap.

[color=#000000]I'm assuming I don't need to look at points or the condenser since I have electronic ignition.

6. Check fuel pressure. I just replaced a bad pump. I usually turn the key to start the pump 3 times before firing the engine. This doesn't fry anything does it? Fuel pressure is fine. Made a gauge out of a swimming pool pump gauge and some fuel lines and hose clamps. Car starts right up without any priming!

7. Anything else I should check?
a. I bought a new fuel filter. Need to install it.
b. need to clean the fuel sending unit.
c. checked the timing. It was fine
d. need to check the ground strap
e. I replaced a hose from the plenum to the fuel rail (old one leaked) and when I drained the gas out, it had black grit in it. I'm guessing this is crumbled fuel line.

I've also thought of just replacing everything above, but I'd like to at least figure out what the problem is.

I've had the car about a year and a half and put about 3,000 miles on it. I drive it at least once a week. I think I'm still in the "shakedown cruise" stage, since it sat for 20 years and the PO just got it running to sell it.

Car now starts right up and runs great!

[mgphoto]

This is bit long, but I've numbered everything, so just answer the number(s) you want/can.

My 1.7L with a Pertronix (everything else is stock) does not seem to run as well as I think it should. Seems to be missing/runs a little rough. It will hesitate and surge just a little, not accelerate smoothly, when I press the gas. This is less of a problem when it is warm.

Lately it's been hard to start. It would crank and want to catch, but took awhile. Today, it just wouldn't start, even though it cranked just fine.

I'm thinking I need to check:

1. Fuel injectors. I've replaced 2, may need to replace the other 2.

2. Coil: the one on there looks like the original. Do these wear out? I've seen posts on how to test them, but I've seen conflicting numbers for results: + to - 0.75-0.81 Ohms, 3 Ohms, and + to distributor output 8-12 Ohms and 10,000-11,000 Ohms. Big difference!

3. Distributor cap: How do I tell if this is worn out?

4. Rotor: How do I tell if this is worn out?

5. Wires and Plugs: mine could be old, but how do I tell if these are worn out?

I'm assuming I don't need to look at points or the condenser since I have electronic ignition.

6. Check fuel pressure. I just replaced a bad pump. I usually turn the key to start the pump 3 times before firing the engine. This doesn't fry anything does it?

7. Anything else I should check?

I've also thought of just replacing everything above, but I'd like to at least figure out what the problem is.

I've had the car about a year and a half and put about 3,000 miles on it. I drive it at least once a week. I think I'm still in the "shakedown cruise" stage, since it sat for 20 years and the PO just got it running to sell it.

1. Possibly, if they produce a good spray should not be a problem.


2. Coils for the most don't go bad, engine won't run, but you will get a better spark with a Bosch blue or a Pertronix Flamethrower.

3. You will see burn marks on the contacts inside the cap.

4. Same for the rotor burn marks and pitting.

5. Yes change the wires.

You need to make sure your timing is correct following the procedure.

6. Yes check the fuel pressure, you shouldn't need to turn the key more than once.


7. Change the fuel filter, change the oil using one containing ZDDP.

Mike

[cgnj]

Hi,
Had the car for a year and with unknown maintenance history? Do a tune-up. It's routine. It's cheap. that takes care of 3,4,5. That includes fuel filter and valve adjustment. Who cares which part is actually causing the problem.

2. Actually they do go bad, otherwise there wouldn't be a replacement market. My experience stone cold dead, and intermittent spark after coil start to get warm. Personally not high on my suspect list.

6. Sit in car, turn key on. Here the fuel pump run for approx 2 sec. Hear gas returning to tank. Now start it? need to keeps cycling key to run the fuel to build preesure to start car?
Now check the fuel pressure. If you took care of the fuel filter already, ths problem may already be gone.

7. Do change the oil and the filter. I personally don't drink the ZZDP Kool-Aid. I store cars at the farm of the oil formulations subject matter expert @ Exxon/Mobil. On cam run in, yes. Normal operation. I think it is a waste of money. Everyone has an opinion. I have mine informed by a man with the CV n this subject, not by something that someone else read on the web, written by someone who may or may not have the expertise, interpreted by another person who may or may not have the expertise.

Carlos

[mgphoto]

Yes forgot the valve adjustment.

[914_teener]

Always have ALL the injectors checked for flow and pattern.

Several places do this and it isn.t expensive.

Inspect your whole fuel system if the car has been sitting.....from the condition and cleanliness of the fuel tank to the fuel lines.

[Mikey914]

Check t he resistance on the cht at room temp (before yhe engine has run or has sny heat). Should be 1600 to1800.
If the cold start injrctor ismt kicking on for warm up, that cou8be an issue.
Easy to check.

[914 RZ-1]

Here is a pic of the cap:

[914 RZ-1]

Rotor pic:

[914 RZ-1]

Pic of end of wire that goes in distributor:

[914 RZ-1]

I've checked the following so far:

1. Fuel injectors are all good. I checked them with a 9V battery and they all click. They all had gas on them, too.

2. Coil looks original. Haynes manual says to test voltage at terminal #15. What do I connect the leads to? The terminal and then ground the other one? Sorry if this is a stupid question; the Haynes manual assumes I know what I'm doing, but this is all new to me.

3,4.: I posted pics, but these seem to look good. Let me know. I ordered new ones from Pelican anyway.

6. Fuel pressure is around 29-30 psi. My gauge is an old tire pressure gauge and doesn't have precise markings.

Can anyone recommend a decent pressure gauge? I may just get a generic one and hook it up to a hose and clamps. Seems cheapest and effective.

[76-914]

2. - youtube has a good video on "How to check/test the coil".
6. - Harbor Freight has a decent gauge in their FI test kit.

[914 RZ-1]

2. I figured out how to check the #15 terminal (one end of the terminal the other to ground. Duh.). Got 10.7V with a HF multimeter.

5. I pulled and checked the plugs. They were dry (so no flooding), and slightly black instead of chocolaty brown, but otherwise looked good.

I got a little tool that you hold on the plug wire and a light goes on if there is current. #1 had no light, so I switched #1 and #2 plugs to see if that made a difference. While testing it, the car started! I thought it might have to do with having the air cleaner off and the 2 big hoses into it unplugged, but I re-attached it and it worked fine.

In the meantime, I found out the tool needs to be held a certain way (seems really stupid, but it will not work upside down). I got a light for all 4 plug wires and the center one when I held it upright. The light was not really blinking steadily; seemed more erratic. I tried it on my 2010 Chevy truck and the light blinked more regularly.

I think I will drive it, while waiting for my parts from Pelican and see what happens.

[914 RZ-1]

Always have ALL the injectors checked for flow and pattern.

Several places do this and it isn.t expensive.

Inspect your whole fuel system if the car has been sitting.....from the condition and cleanliness of the fuel tank to the fuel lines.

I saw a place with Witch in the title. Is that one? What is the name?

Checking the fuel tank is on the list!

[914 RZ-1]

Check t he resistance on the cht at room temp (before yhe engine has run or has sny heat). Should be 1600 to1800.
If the cold start injrctor ismt kicking on for warm up, that cou8be an issue.
Easy to check.

Where does the probe tip go? I put one on bare metal, but where does the other one go?

The CHT is located down by #3 cylinder, right?