Hard start cold or hot but runs good

[northeast dmc]

Well, an update, I cleaned and made sure the frequency valve was connected good, drove the car for 20 minutes, shut it off let it sit, and restarted. It did rev up, after stumbling a little, but this is the first that I have been able to at least accelerate after shutting it down when up to temperature. Not sure if the suggestion of the higher octane, ethanol free has anything to do with it, but cautiously optimistic at this point. Will try it again tomorrow and see how it goes.

[Michael]

Another member here who had issues very similar to yours found the culprit to be fuel injectors.

[northeast dmc]

Another member here who had issues very similar to yours found the culprit to be fuel injectors.

Thanks, I did put new injectors in and new seals for them. I have been driving it every day over the weekend put alot of miles on it, the dirty tank issue would appear to be resolved. I still encounter a hesitation after shutting it off, say to get a coffee, which by the way has anyone come up with a cup holder idea? back to the topic, after going in and getting coffee, come back out it restarts quite easily in my opinion, and start out low speed seems fine, then hesitates for 30 seconds maybe aminute as I try to accelerate, then it clears out and runs fine. Cant quite pinpoint the issue. If it sits as it did Saturday while talking to my brother for a period of time it ran good no issue when I restarted it. The only other thing that I have noticed is it seems to be at alightly higher RPM when it is up to temperature, versus when I first start it. I cant tell you as the tach is all over the place, need to pull the binacle and try to get the connection better on the dash. But by ear definitely higher hot versus cold.?????

[Bitsyncmaster]

If you mean idle RPM is higher when the engine is hot, back out your curb idle screw because the idle speed motor may be running out of range. I had that problem even with the curb idle screw backed all the way out. It turned out my deceleration valve springs were bad. So that let to much air into the system and pushed up the idle RPM.

If one of your deceleration springs is bad that may be causing some other problems but most of the bad springs are both are bad or not.

[northeast dmc]

If you mean idle RPM is higher when the engine is hot, back out your curb idle screw because the idle speed motor may be running out of range. I had that problem even with the curb idle screw backed all the way out. It turned out my deceleration valve springs were bad. So that let to much air into the system and pushed up the idle RPM.

If one of your deceleration springs is bad that may be causing some other problems but most of the bad springs are both are bad or not.

Thanks for the information, it does seem like if I push on the throttle plate arm it does decrease the idle, the deceleration valve springs, are these the ones on the throttle plate arm? And if the throttle arm isnt going back due to the weak springs its possible it isnt tripping the microswitch to the idle speed motor? Sorry if my descriptions are off.

[David T]

If, pushing on the throttle arm reduces the idle, the quadrant link (the short link between the throttle spool and the throttle arm) is worn. You can adjust it to force the throttle arm all the way to idle. Getting back to your hesitation/warm up problem, recheck the vacuum hoses and connections to the CPR. If that isn't the problem you may need to have the CPR re calibrated. It is also known as the Warm-up Regulator and acts like a choke on a carbureated car to improve drivabilty till the motor warms up. It also functions as an accelerator pump and delivers a spike of fuel upon acceleration to quickly richen the air/fuel mixture to prevent hesitation.

[Bitsyncmaster]

Thanks for the information, it does seem like if I push on the throttle plate arm it does decrease the idle, the deceleration valve springs, are these the ones on the throttle plate arm? And if the throttle arm isnt going back due to the weak springs its possible it isnt tripping the microswitch to the idle speed motor? Sorry if my descriptions are off.

The deceleration springs are on the throttle plates. To see them you need to pull off the W pipe. I did have a photo of bad springs but it looks like most of my uploaded photos on DMCtalk are not showing up anymore. If the springs have evenly spaced coils of wire then they are good but uneven spacing shows you they are bad. The springs hold valves on the throttle plates closed until the engine vacuum goes very high.

If your throttle is not closing every time you need to fix that. I found using grease on the springs that close the throttle really helps.

[Ron]

Pics of (bad) deceleration springs

[bytes311]

which by the way has anyone come up with a cup holder idea?

https://www.deloreango.com/us/drinks-holder.html

[northeast dmc]

Pics of (bad) deceleration springs

Thanks, the picture is a great help.