Carburetor warm start issues^*+=

[Dr. Herb Tokyo]

Bouncing idle/surging/hesitation after a warm start (150*+) on a rebuilt carburetor, my old carburetor also had this issue (lasted longer on other carb).
Smooths out after it warms up fully.
I plugged line 8 that T's into the vacuum advance inside the black box & sealed the fuel bowl vent valve (old gooey diaphram never changed after rebuild) this helped signicantly.
I also jumped the terminals permenantly on the carburetor computers sensor, so the computer thinks it is always above 150*...runs a bit rougher cold, otherwise no change.
Next, I am going to try 100% real gasoline.

Curious if anybody else had some knowledge of this issue?

[Dr. Herb Tokyo]

The 3 port thermovalve (17,18,19) was leaking causing the hot start problem, I capped off 18 & 19 before the valve and the hot start issue is now gone, runs very smooth.

Here is a link> 1987 Honda Accord EGR & Vacuum System
for the only aftermarket replacements I have found for the thermovalves, scroll to bottom for all 3 thermovalves for the A1 carb.

[carotman]

Glad you found the issue.

These carbs are a pain. The "later" honda carbs used a similar "PGM-CARB" approach but had a self diagnosis routine in the Emissions Control Unit with a check engine light.

[Dr. Herb Tokyo]

Actually, hot start issue is back.

Obviously the throttle cable.

I would gladly pay up to $78 (or maybe $1million for a new throttle cable + TV cable (joined housing :/)....if it still exists??

[Dr. Herb Tokyo]

Yes, very painful... Think I'll be rebuilding every honda carb right away from now on and I guess use bike tubes & jb weld for diagrams? as they "discontinued"
Piss off honda, I discontinued you in 1997 when you made your last real vehicle, we could fucking care less about your stupid, shiny, AWD gadgeted eggs, make us some frickin parts honda for the Hondas you've already sold.
Ok, I kinda dig those damn pilots though
I'll be on the hunt for a new cable or a good fabrication in the next 24 hours.
I'll post results.

[Dr. Herb Tokyo]

I resoldered the fuel pump/ignition (or fuel cutoff?) relay and all of the other small relays inside the grey box at the drivers kick panel, this was where my warm start problem was from, now it fires up first crank and doesn't bog for first 10 minutes of driving.
Hopefully this helps someone else, I'm guessing all of these 30 year old relays have worn connections.

[Dr_Snooz]

Sounds like the epic main relay problem that occurs on FI models.

[Dr. Herb Tokyo]

yeah, just like the main relay thing which I've been seeing a lot of lately on all different makes and models...
(Temperatures in 90s, all kinds if electrical problems surfacing).
I'll just solder all of these connections right away to eliminate these issues,...to make clear the other issues.
On the 86 model, I struggle to see the point of the Carburetors temp sensor mounted on block, fast idle unloader does the job of bringing engine up to temperature, so why the need to run richer below a certain temp?
Ground the switches wire and forget about it, in my humble opinion.

For the record, I suffered no loss of gas mileage from grounding the sensor & warm start issue solved.

I DID suffer MPG loss from plugging the air jet controllers & connecting power valve to Venturi vacuum, gave the motor a nice rumble and ran like wildfire, but I reconnected everything stock and sold the car.