VX hesitation
 

Hello, I have posted this question on another Honda site (and have gotten some good information) but someone suggested that this is a better forum for a VX question. Question as follows: I have a '92 VX that hesitates badly once it warms up (runs fine when cold). I purchased this car recently, the hesitation was pre-existing. We have done a full tune up, including plugs and wires, fuel filter, air filter, oil filter, oil etc... This didn't help.
I have a spare engine which we have used to swap out sensors and parts. We have swapped out all the sensors on the intake manifold, the distributor, and the ECU, none of this has helped.
The check engine light has never come on, so there are no codes to help diagnose.
It has a 5 wire O2 sensor, which looks newer, I have not confirmed whether it is an NGK or otherwise (have read that Bosch can be problematic). Any help or suggestions on how to correct this problem would be appreciated

First suspects would be coolant temp sensor & o2 sensor.

Based on my VX experience, this indicates bad o2 sensor: I have a '92 VX that hesitates badly once it warms up (runs fine when cold).

There's no reason to think both o2 sensors are tired. How many miles on the spare engine? Was the hesitation the same with both o2 sensors or was it slightly worse with one or the other?

He didn't try a different O2 sensor.

There's a big topic above this one with almost the same title.

Tell baller status I said "what's up".

My spare engine did not come with an O2 sensor. We are going to try testing the existing sensor in the next few days to see if it is in spec. The mileage on both engines is a unknown.

I had a similar problem with my vx engine. Check the tps sensor. should register +.5v with engine off and throttle completely closed, and +4.5-4.6v at wot. Adjust the sensor until you get the correct values.

I looked at the O2 sensor today. It says "L1H1 Japan", which I assume is the OEM NGK/NTK. The mechanic I am working with was not sure how to test it, or what was considered "in spec", any help on that would be appreciated. We will also test the TPS sensor as suggested. Thanks

I had a bad hesitation problem that turned out to be the result of a dirty throttle body. My mechanic cleaned the throttle body and that did the trick.

I also had a bad hesitation that turned out to be severely retarded timing. It may sound stupid, but it's easy enough to check and cross off your list of potential reasons.

We cleaned the throttle body and checked the timing, they didn't do the trick. Finally purchased a new O2 sensor (NTK L1H1 for $99 from www.autopartsdirecttoyou.com), it seems to have worked. There is still some subtle hesitation but I think I can live with it. Now I need a road trip to see what the mileage is like.
Another question: what should the engine idle at when warmed up? Mine seems to idle at about 500 rpms or lower, it has not stalled yet but feels like it wants to.

does the sensor you bought have l1h1 stamped on it? the one i saw on that site were the 92-02 version... i'd be interested in hearing how it works out for you!

>>>>Finally purchased a new O2 sensor (NTK L1H1 for $99 from www.autopartsdirecttoyou.com)123, it seems to have worked. There is still some subtle hesitation but I think I can live with it.

Wow, that's the cheapest price I've seen on L1H1!
Is it really authentic NTK L1H1?? We need more info on that sensor ! :)

Stock idle speed is 600 +/-50. You need a diagnostic tach because the stock tach just isn't accurate enough.

Any small vacuum leak or bottleneck under the hood of the VX will cause a driveability problem ranging in severity from a slight hesitation to serious bucking. It's a result of Honda pushing this car and it's technology to the ragged edge for maximum economy. That is why the VX got very low reliability ratings compared to the rest of the Honda lineup; which in turn motivated Honda to perfect it's system with the introduction of the HX (lots of backup strategies and self diagnosis).

The O2 sensor was stamped NTK L1H1, and seems to be working fine. The sensor appears to have been repackaged by a domestic company out of Long Island City (can't remember the name and I don't have the package with me). Thanks for the confirmation on the idle speed, I will confirm it with a diagnostic tach and double check for vacuum leaks.

I'm not as tech savvy as some of the others on the site are, but I can tell you that I had similar issues to what you've described with my 92 VX for a couple of years before I found this site. The guys chimed in with the "replace the O2 sensor" proposition. I followed their advice, changed out the sensor (even though I paid more than I should have for it), and the car behaved much better immediately. The moral of the story for the VX is that O2 sensors on these cars do tend to go bad after several years, and the device is a major part of the VXs outstanding fuel economy.

Another device that can affect how a VX engine runs is the Electronic Air Control Valve (EACV), which sits at the top of the engine between it and the firewall. The EACV can get clogged or dirty, and this can impact idle rate or make the engine idle rough. There are links on the site as to how the device can be removed for flushing out with brake cleaner. You can also get replacement screens, etc. From OEM Honda parts websites such as Bernardi Honda.

One more thing: make absolutely sure you have the correct spark plugs installed in your VX: they are not the same as those used in other Civic models. Use NGK V-Power Plug #ZFR4F11. If you use others your car can run much worse than it should.

you can also slip your finger under and into the egr valve and manually open it to check that it moves freely and evenly...
holding it open at idle will make the car stall
but you can play with it a little...

Hilarious Use of Language Alert: Of Course it sounds stupid. It's Retarded!

Sorry. I couldn't resist.

I've had 2 VXs, a 93 and a 94, both had hesitation issues after 150k, or thereabouts. I replaced the after market plug wires with stock wires and that solved it for me.

vx throttle problem
 

Hi i'm a new member from Qu?bec city in Canada...same problem...my car is ultra clean, but i still have iddle problem...up and down...between 900 rpm up to 13-1400.rpm...and goes down...and when try to accelerate seems to loose power...i have to press more...and feel a kick and accelerate...???parts changed..NEW...EGR, AICvalve, oxygen sensor, intake gasket, temp.sound(gauge)new tps...only the throttle body is change but for another used...so maybe? by the way my VX is a 92, with 207,000 KM...yes we are ine kilometers...please help...thanks

Re: VX hesitation
 

I'm having the same problems with my vx as well.

almost 300k kms on my original engine. did all the tune up stuff but still has the slight hesitation.

the power does not come on smooth when the engine is warmed either. like if i go 20% throttle to slowly speed up, there will be a flat spot in power... then, power will kick in. it's quite annoying.

the emissions tester did say that i have a little exhaust leak... and that can cause a/f ratios to fluctuate due to incorrect o2 readings. i think i will tackle this first. PITA to remove hot parts though!!! ughh.

Re: VX hesitation
 

Hey VX owners. I wanted to know what your car idles at when you start it up. Mine idles at 1500 RPMs. Then it slowly goes down to 700. Is anyone else having this issue?

Re: VX hesitation
 

Stock plug wires, I'm thinking. They are quite different from aftermarket ones. Shape, size, etc. I'm gonna pull the wires from my parts car (stock ones) and try them against my aftermarket jobs.

I've had similar problems since owning the car. Some things improved it, others didn't. Still not what I'd call 100%.
B

Re: VX hesitation
 

This is normal for a cold start, and since you're in MN and the weather is getting colder it's triggering the cold start procedure for our Hondas.

If the weather is below about 50?F it will trigger the cold start which is to idle at ~1500RPM for a minute or two and then slowly decrease to the stock idle of ~600RPM when engine temp has warmed up.