crank no start perplexed, what else Options

[Wew]

Hi all,

I have read and done a bunch of research and still no luck getting my ride to turn over.

1973 2.0 with fuel injection. Has a 2056 build with a performance cam. (still within parameters for a fuel injected car)

Battery at 12.6 Volts
Throttle body serviced
Compression: 130 all four cylinders
Spark: yes
Timing: checked and set at 0 TDC. (will set @ 27BTDC at 3500rpm when I can get it to run)
123 ignition rotor pointing at #1 spark plug wire.
Fuel pressure 28 PSI
Checked injectors and they are squirting fuel.
I do not have the proper CHT which I believe should measure at 1300 ohms.
The one I have measures at 2700 ohms.
I had checked the MPS and if memory serves me right it held air for quite a long time at 17 or 20 psi???? I could be wrong on this as this has been a while.
Have checked for vacuum leaks and done a smoke test when car was running and no leaks found.
All new vacuum lines with clamps.
The car would drive fire right up cold and idle rough. It would buck under load and also didn't start if it was warm.

What changed?

I took out the Throttle body and saw fuel in the plenum which I believe is fuel from the cold start injector.
In all my infinite wisdom I ended up messing around with the throttle position sensor and thought I got it back to its correct setting using one of those line testers like Gary Cotton has used in his video. Maybe I am screwing this up but I don't think so..
I also realized that I had the 123ignition vacuum port connected to my retard side (rear) on the throttle body. (advance was plugged). I changed this and put the smaller vacuum line on the 123 ignition and attached to the advanced port on (front) of the throttle body.
Now I get no love... It just cranks and cranks but will not start. (IMG:style_emoticons/default/chair.gif)

I am aware that this is the incorrect CHT. It doesn't seem like these are available in the 1973 version any longer. Any solutions or mods I will gladly take on. Was wondering about one of those potentiometer to draw down the ohms from 2700 to 1300 if that is possible. If so, any specific recommendations on what you used and worked would be appreciated.
Maybe I beat up the TPS. I had purchased it new from 914 rubber and has gotten very little use other than me messing around with it and the short stops and starts trying to get it going. I have attached a couple of pictures.
I don't want to just start throwing parts at this.. It has to be something I did.
Where I am at is I can't even try and make it run better now because it won't even start.
Ugh (IMG:style_emoticons/default/headbang.gif)

I have also included a link to a youtube video I shot prior to changing the vacuum hose from retard to advance. You will see it idles o.k and then when I accelerate it gets sticky and remains at a higher idle. I have checked the throttle cable and it is not wrapped around the clutch cable.
If I had my druthers I would go back to what it was, but again it would flatten out or buck when I would accelerate and hard start once warm.


I lack the intuitive mechanical skills that many other have on this site and am hopeful I can get some advice on next steps.

Much appreciated.

Gary


https://youtube.com/shorts/idT2vM8uaOg?si=MixjnXL2zrQaNrnV

[Superhawk996]

Recheck the basics

Confirm spark at all spark plugs.
Confirm proper firing order of spark plug wires.
Will it fire or at lest cough using starting fluid with injectors disconnected?

Cold start valve doesn’t come into play until temps are near freezing. Temporarily disconnect the cold start injector electrically. Test it to make sure it isn’t leaking.

Due to the CHT cold resistance the engine is already going to try to start too rich - you don’t need the cold start injector making it worse.

Do you have the ballast resistor for the 73 in line with the CHT? Have you verified the resistance of the ballist resistor to make sure it hasn’t gone open circuit?

[rjames]

The car should start and run with the TPS disconnected.
It’s ok to have retard connected to the 123 dist, just make sure you set the 123’s DIP switch appropriately. (And make sure it’s set correctly for the dist it replaces). If you use the retard port on the TB, make sure you plug the advance port on the TB.

[Ruff914]

Test for spark on all cylinders and spark timing. Use a timing light to do this. An old timing light reveals a lot of problems.

[mb911]

Basics should also include key switch function cranking vs key off. How many of us have had issue with that over the years.

[Wew]

Thank you very much for all of your input. Will apply all suggestions and report back.
Much appreciated!

[emerygt350]

All of the above. Your car can start and run without the TPS or even the mps vacuum hose attached. And I would actually suggest disconnecting the TPS while you are testing. If it is borked bad enough it will stop the injectors from firing.

Does it try to fire or just turn over and you get nothing?

Does it smell gassy? Careful because you may be filling your crankcase with fuel and that can cause badness.

[Lockwodo]

I'm wondering if the timing is way off. It was running and now it isn't, did you do anything in-between to change the timing?

[ClayPerrine]

I am going to repeat a piece of wisdom I got from my father when I was 17. I changed the carburetor on my 69 Firebird, and was trying to get it to start. When he showed up from work, I was busily jacking with the timing. He asked me what I was doing. I told him I replaced the carb and now it wouldn't start. He asked me why I was messing with the timing. It was fine when I started changing the carb. Then he said "What was the last thing you f*cked with?" Now my father normally didn't swear. But he would when he wanted you to remember it.

So now I am going to ask you.. "What was the last thing you f*cked with?"



I would suggest checking the timing first. Zero degrees is way to retarded to get the car to start. If you are still running points, you can static time it to 9 degrees (L-Jet cars were timed to 8.5 degrees) and that should get the timing close enough to start.

To static time an engine, set the timing mark on the fan to 8.5 degrees. Then disconnect the green wire from the coil, and hook it to a test light. Hook the other end of the test light to the positive battery post. Rotate the distributor until the light comes on, then back it up until the light goes out. Lock down the distributor.

Hope that helps you out.

[Wew]

Hi all,

I have spark at all 4 cylinders.
Spark plug wires in proper order
Manually turned engine again to 0tdc rotor pointing towards spark plug 1. 123ignition turned counter clockwise with black wire to coil disconnected and green light illuminates. Tightened down cap reinstalled.
Cold start valve disconnected. No leaks.
Still crank no start.
Ignition switch working.
Gas tank is low and am wondering if all of this could be from bad gas?
Next step it to add staring fluid with injectors disconnected.

Thanks again and will report back.

[914sgofast2]

The "Car Wizard" channel on You Tube recently posted a very appropriate video about the problem you are facing about an Audi that would crank but not start. Since you say your 914 cranks but won't start, your situation is similar. First, take out the air filter and then spray some starting fluid into the car's intake. Crank the car over and see if it starts. It it starts and runs for a few seconds, then the problem is in your fuel system. If it doesn't fire up at all, then your problem is in the ignition system.

[Wew]

I am also interested in your opinions of the link to the video I posted. Is there anything glaring the way it sounds or how I pulled on the ignition and is stays at a higher rpm and very slowly come back down.
Just curious and thanks.

[Wew]

The "Car Wizard" channel on You Tube recently posted a very appropriate video about the problem you are facing about an Audi that would crank but not start. Since you say your 914 cranks but won't start, your situation is similar. First, take out the air filter and then spray some starting fluid into the car's intake. Crank the car over and see if it starts. It it starts and runs for a few seconds, then the problem is in your fuel system. If it doesn't fire up at all, then your problem is in the ignition system.

I will check out the video!
Thank you

[rjames]

I am also interested in your opinions of the link to the video I posted. Is there anything glaring the way it sounds or how I pulled on the ignition and is stays at a higher rpm and very slowly come back down.
Just curious and thanks.

High idle is usually associated with timing, AFR tune, fuel pressure or a vacuum leak. Since idle rpms stay up after releasing the accelerator cable, I’d remove the air box and see if the butterfly is closing all the way. You can start and run the engine with the box and associated hoses disconnected without impacting anything.

[Dave_Darling]

So now I am going to ask you.. "What was the last thing you f*cked with?"

This--absolutely this!

And to add to it (not from direct painful experience or anything, not me! (IMG:style_emoticons/default/wink.gif) ) What did you bump or move while you were f*cking with that last thing? Could a wire have gotten unplugged? A hose knocked loose?

--DD

[Wew]

I recalibrated the throttle Position sensor in hope of helping with idle, and the acceleration flat spots or bucking along with the slow deceleration of the idle. Once I did that the. Ar started one more time but had an awful idle and sounded horrible. I turned it off after two minutes and hasn’t started since.i am scouring the engine bay for open vacuum sensors disconnected.
I disconnected the fuel injectors, the cold air injector and the tps. Air cleaner removed and sprayed with starter fluid. Cranked it and had one sound of trying to start and the. A massive backfire that scares the crap out of my dogs. Now I try again and get a little spitting sound occasionally but still just cranks.
I also followed 123ignitiins instructions for a new install which calls for 0 tdc and the green internal distributor light coming visible when turning distributor body counter clockwise. This has been done.
Frustrating and all you input is much appreciated.

[emerygt350]

Starter fluid is your friend.

[Superhawk996]

I disconnected the fuel injectors, the cold air injector and the tps. Air cleaner removed and sprayed with starter fluid. Cranked it and had one sound of trying to start and the. A massive backfire that scares the crap out of my dogs. Now I try again and get a little spitting sound occasionally but still just cranks.

So you now know: you do have spark (at least in one cylinder) but you don’t mention if you’ve verified all 4 and the state of the plugs. Post photo of plugs - I’m betting very black and sooty.

We also know you have a fueling problem since it at least coughs & tries on starting fluid.

Not surprising you have a fuel problem based on previous description of fuel in plenum and the fact that your CHT is wrong for a 73’

Again - you haven’t confirmed whether or not you have a ballast resistor and whether you’ve checked for an open circuit.

If the CHT goes open circuit the mixture goes massively rich and will not start and will also quickly foul the plugs.

Your previous video has no bearing on what’s going on now. Forget about the past and focus on the current symptoms.

You’ve gotta’ follow the data and do the diagnostics.

[Wew]

Thanks for the input.
I have checked spark and have it on all 4 cylinders.
I did remove all 4 plugs and yes there was some black soot on all 4 plugs. Spark plugs are fairly new within 3 months with very little running time. Maybe half hour.
I cleaned all four of the plugs wiping soot away and used fine sand paper to clean off any unseen goop that could hinder spark.
I do have the ballast resistor that measures 270 ohms of resistance. Since the CHT already measures at 2500 and if I add the ballast resistor it increases the resistance another 270. My understanding is I want the resistance to go down to 1300 ohms. How do I accomplish this?

Optima red battery (4 years old) is losing voltage quickly to 11.9. This is the 2nd time in the last 3 days I have had to charge it to get back up to 12.6volts. After cranking on it for an afternoon I measured it and it dropped to 11.90 again Based on this I think it’s time for a new battery. Honestly I haven’t been impressed with the battery and am wondering what you all prefer?
So next steps tomorrow are
1. New battery
2. Someone please confirm I am setting the 123 ignition properly.
3. Check all vacuum and connections.
4. Hope someone responds on how to lower the resistance on the CHT (2500 current and want to reduce to 1300) How I measure the CHT is ohm meter (red wire) on connection end that would plug into the wire that goes to the ecu. The black wire goes on the negative side of the battery. This is how I am getting my readings.
I believe the above shows I don’t have an open circuit, although I could be wrong and open to public embarrassment and humiliation. .
Will also check fuel filter, although I am getting fuel to all four injectors and fuel pressure is at 28 psi, and the pressure drops to 20psi fairly quickly after I quit cranking the engine and stays there for a couple of minutes until it starts its descent to zero.

Thanks again!

[Superhawk996]

The ballast resistor works against you when the engine is at ambient by raising resistance by 270 ohms higher than the already high value (approx. 1300 +270 vs 2500 + 270)

However, when the engine is warm and the CHT goes to say 100 ohms, the engine is going to run lean(er) without the ballast resistor present. At that point not having the 270 ohms in the circuit is a much bigger difference as a percentage (approx 100 ohms vs 370 ohms so almost 4x more)

See attached plot for CHT 012 vs 017 (correct for 73’). Not how they converge when hot.

The way you’ve measured CHT so far is fine but be aware that you could still have an open circuit between the wiring right at the CHT and the ECU. Do not assume the wiring is OK. There are a lot of very crispy 50 year old harness's out there. I’d be looking at the wire very carefully. Chances are it’s probably not broken given it was running previously but at some point you may have to measure it at the ECU to verify.

I would replace the plugs before I replace a battery. Plugs can get fouled and even though you clean them they still don’t fire properly. However, given the coughing on stating fluid I would still focus on whether you’re flooding it during cold cranking. Have you pulled the plugs immediately after cranking and failing to start? Are they soaking wet and gas coated?

It isn’t unusual at all to have a battery drop slightly below 12v after an extended period of cranking. Don’t get distracted and start chasing ghosts. Just keep charging the battery as needed.

To get rid of the question about the CHT. Get a 1300 ohm 1/2 watt resistor (or dial in a potentiometer to 1300 ohms) substitute that for the CHT. One side to the harness, the other side grounded to the block (fan shroud, or battery negative OK too). The adjustable potentiometer is the better way because assuming it starts you can dial the pot down as the engine warms to keep it running.

Can’t help you on a 123 and how to slightly advance your static timing. I have never had one. Sorry. I’d assume it’s done via DIP switches or their app depending on what model you have.