History of my 92 VX troubles (and help request)

[GasSavers_Jack]

Ok here is my update. I pulled my ECU it is the P07. I also soaked my ICV in throttle body cleaner for a few hours. It didn't fix my idle problem but it is better. Also my muffler 1/2 fell off so I pulled it the rest of the way off and ordered a new one.

I will get the compression test done once election day has passed. Until then there is just too much stuff to do.

[GasSavers_Jack]

Here are my compression numbers...... 160 right across. Well the rules that out.

[GasSavers_Ryland]

I think I'm having simaler problems with idle bounce, I plan to check again for vaccum leaks, my only thought is that my PCV system might have a leak, it's so hard to get to that lower hose, I have a new grommet and everything, I just can't get in there with my big hands, I'll try cleaning my ICV as well and see what that does, it sounds like I'ver replaced all the exact same things as well, and each one helped, but didn't solve the problem, and there isn't that much left.

[onegammyleg]

Originally Posted by theclencher

Turns out a heavy build-up of carbon, soot, and gook in the intake manifold behind the throttle body caused it! .

I think you would find that there was a small vac port that was blocked with the goop.

A reduction of the intake size by the amount you said shouldnt affect anything ,,and if it did ,it would be during wide open throttle positions where the restriction restricts air flow , not during mid speed cruise conditions where the air flow volume is MUCH less.

[onegammyleg]

Originally Posted by theclencher

What you say makes sense but that wasn't the case. None of my vac ports were plugged.

If you sure that no vac ports were blocked , then the only other idea that I have is that if the goop was thick right up to the butterfly that could cause a problem.

If the throttle was partly open (during cruise) the throttle position sensor would see it but the air could be blocked or restricted (by goop) at this very small throttle position.
The TPS would not match up what the other sensors are seeing.

Idle would still be good because its often bypassed the main butterfly anyway.
Its only at very low butterfly openings that there is any real airflow along the walls of an intake., but only in the very near vicinity of the butterlfy.

Normally most airflow is in the middle of the port.

But for this idea to work it would realy REALY have to be gooped up against the where the butterfly rests .

[krousdb]

Originally Posted by Jack

Here are my compression numbers...... 160 right across. Well the rules that out.

FYI, Mine were 175 - 180.

[Gary Palmer]

Originally Posted by FormulaTwo

Make a intake manifold leak tester
It is very very simple and easy to make

http://www.mirage-performance.com/Ec...aks/index.html

Just hook it up to an air compressor/ bike pump
Pump the air into the intake manifold, and then spray windex on the manifold/hoses and watch for bubbles

No bubbles/ no leaks

Hooray

I have the same idle problem, But i feel like it is due to my egr not being connected. Which will be fixed soon. and I will let you know.

I understand the principle, I think, behind this tool. However, where I get lost is how you can keep all of the intake valves closed, so that the air pressure you are putting into the intake acutally comes out the leaking hose, instead of just going down the open valve.

I had a vacume leak which created a lot of symptoms similar to what you've described and I never could find it using carb cleaning spray. I finally just got dumb lucky, and found it because I was looking for something else, in a difficult spot, which finally allowed me to see the last 1/8 inch of the hose that had become disconnected. It looked like it was connected, from every other angle.

[onegammyleg]

Originally Posted by Gary Palmer

where I get lost is how you can keep all of the intake valves closed, so that the air pressure you are putting into the intake acutally comes out the leaking hose, instead of just going down the open valve.

Your exactly rite , and thats where the whole idea falls into the poop.

Another way (the rite way) is to use a threaded adaptor to fit the spark plug hole and connected to an air compressor and presure gauge.

Its called a leak down tester.



With it you can do very accurate asesments of valves and rings, cracked pistons , head gaskets , blown heads .., and also depending upon the cylinder its conected and the position of the valves it will show either intake or exhaust leaks.

Its a tool that gets used after every 1/4 mile pass on high powered drag cars to see if they should strip the engine down and rebuild it before the next run.

A real valuable tool.

[GasSavers_Ryland]

the other day I finely replaced the gromet that fits in the oil seperator box on the back side of the engine that is part of the PCV system, the gromet that I replaced is part number 3 here http://www.hondaautomotiveparts.com/...EATHER+CHAMBER
after replacing this gromet with a new one my idle became more stable, and idles smoother at lower speeds, and the engine seems to be over all more happy, I was suprized at how hardened the gromet had become over time, creating not only a vaccum leak that I could not hear (you can hardly even see that part of the engine) but it was also alowing crank case gasses to escape.

[surrf_boy]

Just some info for VX owners. I just purchased a 92 VX and at 1/4 throttle, between 1500 to 3000 rpm it would sputter and hesitate. When it started to hesitate, if I gave it full throttle, it would clear up and accelerate, but trying to maintain a steady speed would be difficult.

I didn't get any check engine lights at all. The first mechanic replaced the Throttle Position Sensor. That didn't fix it so the Honda dealer looked at it. They replaced the ECU, and did conitinuity check on all wires and couldn't find the problem, so I brought it home.

I checked the TW sensor(temperature coolant sensor) and observed that it had 2.4K ohm resistance when cold, and when it got to operating temperature, it was 299 ohm. They symptoms above acted like it was running to lean. It would have difficulty starting when hot on a hot day, and had a very low idle. Either the O2 sensor is no longer calibrated and running to lean, or the TW sensor is out of range. I added 150 ohm resistance in series with the TW sensor, to bring hot temperature resistance to 450 ohms, and guess what? I no longer have hesitation, it starts easily when hot, has plenty of power. I tested it with 100 ohms, and still had hesitation, so 150 was right on, withtout throwing any engine codes.

Does anyone know what the TW sensor should read when the engine is at operating temperature??

I do have an oxygen sensor on order, an L1H1, and I will replace that anyway and see if that clears up the problem without the extra resistance, and I will post the results. I will also post the mileage with the resistor in place, since it may be running to rich.