VX shift light question
 

I searched for a post on this but didn't find a good match. When I got by VX about 1700 miles ago I got FE in the low to mid 30s. Since then I've put the correct plugs in, installed and calibrated the TPS, new O2 sensor and cleaned the eavc (leaking air internally) and will replace it this week. So far I've cured the engine lag and I suspect that the new eavc will bring the idle under control. To date the best tank I've gotten is 43mpg and yesterday it came to 37mpg. Not bad for a Civic but crappy for a VX.

I've noticed since I got the vehicle that sometimes the shift light works and at times it doesn't. I use my car for running the same 120 mile RT route 4 times a week and I've noticed that on the trips where the light isn't working my gas mileage really stinks and I can watch that gas needle drop. On trips with the light working the needle barely moves and if in a given tank the light works a lot, I can count on decent mileage. When the light doesn't work so much the car consumes a lot of gas. Maybe I'm crazy, but its starting to bug me a bunch. I drive the same route the same way and FE is sometimes great and sometimes it stinks. I am aware that the gas gauge isn't exact and that the first part of the tank goes farther than the last. Trust me that is not the issue here, I've had plenty of vehicles with these kind of gauges and this is not causing the variance in distance travelled per gallon. So can the light issue be indicative of an underlying problem, maybe a bad ECU? Does this sound familiar to anyone? I hate to spend more money on a car that is supposed to save me money, but if that what it takes to get the most from this thing then I'll try it. Thanks. :confused:

Oh yeah, one more thing.... when the light is working the engine actively hunts for a good idle speed (it goes up and down) when in neutral. When the light isn't working the engine idle remains high and doesn't hunt.

Maybe the light being on or off has to do with ecu having a code? I'm not sure really, but assume your CEL light on the cluster is burnt out, and try jumping the service connnector to see if there is a code stored in the ECU.

On my VX the shift light has never worked, hopefully I'll have success removing the dash bezel to fix it soon.

my shift light is pretty wonky too. I don't need it tho, do you? Shift by your speedo, not your tach, for best FE. On flat it should go something like this if you have the '92-'93 civic VX (I believe higher mph shift points on the '94 '95 VXes)

shift into 2nd gear at 12mph
shift into 3rd gear at 20mph
shift into 4th gear at 25mph
shift into 5th gear at 31mph

Seems rather unlikely your shift light alone is affecting your FE. You say you are not changing at what speed you are shifting gears when the light is not working?

I am going to replace my ECU on my car in a few weeks. I will let you know how it goes! My idle is still high and I think it's the ECU.

CEL light works, brand new 74 bulb a few weeks back. there was no code after resetting after the new O2 sensor, but I'll check it out. Thanks.


There is now way I could possibly shift into 4th at 25, 3rd is dodgey at that speed and 5th at 31???? Surely you jest!!! Hmmm... if those ARE supposed to be my shift points, me thinks something else is wrong. I saw a TomO post talking about the effects of being off a tooth on the timing belt, I think he said it would still be drivable but underpowered. Maybe this could account for some of the FE problems. The previous owner got new timing belt installed by his Honda dealer... maybe they got it on wrong. I'll try to ferret out the post.... something about a 16mm socket and cylinder 1....

the shift light works on vacuum pressure. if the vacuum is low and you are not in top gear, the light will come on.

a vacuum leak would stop it from working. when you replace the eavc then i suspect your fuel economy should get right back to where it is supposed to be in the mid to upper 40s.

good to see that you turned that vx around!! also, what are the tires you have on there? a cx, vx, or hx with a tire with that would belong on any other civic or integra will cost you at least 1-2 mpg, even if both are the same brand and model.

Thanks, I hope you're right! The tires are 175s not165s, but my FE numbers are adjusted for the difference. I also have steel rims. I just got 2 vxrims and am looking at a set on ebay as too. I plan to swap when I get a set of 4. I would just dump the tires, but the previous owner had just put them on and they still had their whiskers when I bought the car. I figured that replacing them was prolly a false economy, but I havent crunched the numbers.

175 isnt that bad at all, i meant something like 185-205. i should have specified newer civic wheels:)

you will be ok with the 175s and they will get a lot better as they age, not to mention they are safer. keep new tires properly inflated though so they wear even. dont inflate them rediculously so the center wears faster than the edges.

I remember the post, I'll try to dig it up. I am intensely curious how other VXers drive their VXes. I also wonder if my gearing might somehow be different than other VXes? Not sure how this could be but I'm already at 2000rpm at 60mph. It would be great if we posted videos of ourselves driving! haha. So what RPM/speed are you shifting at?

I believe my RPM translation of those speeds are as follows:

shift into 2nd gear at 1800 rpm
shift into 3rd at 1600 rpm
shift into 4th at 1500rpm
shift into 5th at 1500rpm

what RPM are you at at 60mph?

here's the timing belt thread you requested

https://www.gassavers.org/showthread....timing+belt+vx

Thanks for the link but I don't think thats it. The one I'm refering to talks about the position of the rotor when cylinder one is at TDC. i haven't been able to find it again.... yet

you mean position of the pulley?

LOL, and me running around on my 215/50/13s, shame on me. But I use the wider tire in my spirited driving events at the autocross as well as my daily commute. It helps me corner...at the event and on the streets, lol. Tire pressure is the key though. I'm running a minimum of 48psi in all the tires during my daily commutes, and on days that I have autocross events, I run it up to about 51psi.


Definitely check your timing to make sure it's spot on.

The upshift indicator (as Honda calls it) reads the MAP sensor, TPS sensor, and rpm signal to determine the best upshift timing.

The Rotor trick is really only good for making sure you have the spark plug wires in the proper order. The rotor contact area is wide enough for a 15° timing spread and isn't great for telling if the timing belt is set correctly. Best thing to do is:

• Take off valve cover
• Take off upper timing belt cover
• Take out the spark plug closest to the timing belt cover (#1 spark plug)
• Gently place a long thin screwdriver into the combustion chamber through the spark plug hole
• Rotate the crank pulley counter-clockwise until the single slash mark lines up with the TDC mark on the lower timing belt cover (Watch the screwdriver to help notice when the cylinder is at TDC)
• Check the camshaft pulley to make sure the "TOP" is at the top, and the angled mark on the lower left of the cam pulley is pointing at the plastic indicator on the inside upper timing cover.

With my 94 VX having over 336K miles on it....on a flat road and about 10% throttle, I will be in 5th gear by the time my speedo reads 30MPH. And that is with the upshift indicator illuminating to tell me to upshift as well. So when your VX is running right the same should hold true for you on a flat surface.

Hope some of this helps you out, dogncatboy.

I recently changed all of my vacuum lines with new 1/8th inch fuel line (bought fuel line by accident). But I found out that the fuel line fits more snug than the vacuum line and resists collapsing better. Vacuum line is cheap, and definitely worth the 1 hour (at most) it takes to replace every bit of it under the hood.

Thanks for the info TomO! I will check it out this weekend. How much fuel line did you need to swap out the rubber? I may as well do that while I'm at it.

So you think the shift light issue is all in my head? I'm gonna start a notebook to see if my correlation is way off or spot on. I have a hard time believing that my mileage is consistent with and without the light. Me thinks there is something else failing here.

I had to buy a 25 ft. roll of the vacuum line, but that only cost me $7. Usually at an autoparts store, it's around $1 per foot or less. I think I've used less than 7 ft. of it for my car.

i should rephrase. tire width should depend on the type of driving you do. if you do not plan on banging around winding roads to maintain speed while going down hill, lower resistance is better.;) so i assume you race street mod? i used to when i had my hatch... the memories. anyway, why not pick up r compounds for the track and get something better for fuel economy for the daily commute?

this is interesting particularly with the models that have the shift light...

My shift light is wack.. I think it because I'm running the wrong tranny.. My 89 hatch is set up with the vx engine and a dx trans..

I need to find a cable HF trans. :(

Do I need to get a new valve cover gasket? I like to be able to put it back together once I'm done.:) I was looking at the manual and it seems that actual replacement might be outside my comfort zone. If its off I think I might need to take it to a mechanic to get it fixed right.

You do need to pull up on the Valve cover a little to get the upper timing belt cover off of the cam gear, but you might be able to get away with just tightening the cover back down without replacing the gasket (I know I did once, but the gasket was brand new at the time). The gasket is easy to replace, no trick to it at all. Just use a little gasket adhesive to make it stay stuck to the valve cover, and make sure no oil or gasket residue is left where it seals onto the head. Most importanly, don't tighten the valve cover down too tight (my rule is to only use a 1/4 in. drive ratchet) or you will break or strip the studs holding it down. The sparkplug hole gaskets are a pain, but with some time and a hammer, they can be done by anyone.

Dogncatboy - The valve cover gasket is reusable as long as it is wiped clean of oil and has no tears or cracks in it. Using a 1/4" ratchet is a good idea for tightening the valve cover bolts. I don't remember the exact torque spec for those bolts, but I do remember that it is in in./pounds, not ft./lbs. Best to under tighten, have a small leak, then slightly tighten more until the leak stops.

thisisntjared - I don't run r compounds on my Enkei conpe 8s because they are super light (ever so slightly lighter than the VX alloys), wider, and (in my opinion) look nicer than the VX alloys. I run a 215/50/13 on them because most other tire sizes available in a 13" are too skinny and tall. They aren't recommended to be mounted on as wide a rim as the Enkei is. Besides all that, it's my own little form over function nicety that I have on my car. The kicker is, they actually have quite the function as well. ;)

yea i was going to say i know someone who runs a 215/50/13 tire in the auto-x but he runs the r compound for his festiva. that car keeps up with evos.

so you do run street mod? i could understand if you were in sts but that class doesnt allow the cf hood. if i were racing that car in sm, i would use those wheels for the r comps and get something cheap and easy(vx) for the dd.

what is the eavc?

my vx does the idle hunt as well. I cleaned the IACV but it didnt do anything.
I also notice the idle bump up if i press on the brakes real hard, could this be a bad booster?

TomO: My first mechanic, the one who did the valve adjustment, said you generally don't want to reuse the valve cover gasket. But apparently mine was glued back on. Not sure if he used a new one or not - kinda looked like the same old one. The new mechanic I have been seeing who fixed my brakes and cleaned by throttle body said it was a no no to use glue. (he also thinks the first mechanic I went to is a terrible mechanic)

Anyway, just was curious what your thoughts on that were.

Robbie: Did you clean the throttle body? That fixed two problems for me. Stopped the idle from hunting and fixed the sticking idle problem I had.

Robbie,
eavc - electronic air valve control
It sits behind the intake manifold and is usually clogged with carbon.
There is a steel mesh (or two) that covers the port. If you take it out
and you can't see a shiny steel mesh, but instead black carbon, then it's
most likely clogged. Cleaning it fixes idle issues. So this is what you can
check if you have idle issues (like hunting).

Gary
93 Civic VX - 56.12 mpg personal best

The OEM Honda valve cover gasket is reusable as long as no gasket sealer is used on it. It is a silicone gasket and the only time it should be replaced is if it tears. Otherwise while it is off, just a quick wipe with a dry/clean cloth will get it ready to be used again. Make sure to wipe off the mating surface on the head as well.

I'm no longer retarded...
 

OK, my girlfriend would argue with that. Me and a friend checked out the position of the belt last weekend and discovered that the timing belt was not positioned correctly. Being a chicken#$&*, I paid a trustworthy local garage to look at it as well and they confirmed the diagnosis and made the repair. Not cheap. Apparently my timing has been retarded [thats what he said] this whole time. My car now drives like a whole different car. Much peppier, it no longer feels sluggish it seems to be able to shift sooner at lower rpms without bogging. Funny thing is that the belt had been installed for the PO by the Fort Wayne Honda dealer. Goes to show you that dealer wrenches don't know all that much. I won't be able to check the mileage until next week, but I've got my fingers crossed for my first 50mpg tank.

Apparently I did the same thing with my timing belt. It was one tooth off and when I drove through the santa cruz mountains, I knew something was wrong. Had to do it all over again....

I changed about a dozen timing belts in my life and the vx was the first one I was off a tooth.

Gary

i changed the timing belt on my parents crv and the intake cam was off by a tooth. it drove ok for a day then it started pinging. my dad told me and i identified it immediately and told him not to drive it till i could work on it.

he drove it to the airport, so i couldnt work on it then came home and valves were bent and whatever else with the head... man that got expensive fast!!

my point is you are lucky that all you had to do was just have it reinstalled!

Often improper timing belt installation allows the gears to jump teeth, and when the timing gets too far off, that's when valve damage can occur. I've seen LS motors (same as the CRV motor) run being many teeth off (timing belt teeth) and with no motor damage. Chances are yours was a little too loose and skipped more teeth, causing valve damage. That being said, I've seen a D series motor already being off about 6 teeth, being able to run (but pinging a LOT), and no engine damage. It's all about luck with Honda's and the timing belts it seems, but in general, make sure that it's perfect before you run it to make sure no damage occurs.

One tooth off shouldn't cause valve damage. I agree what probably happened was that the belt slipped a few teeth during operation causing valve damage.

Gary

Now that my timing belt is on right, my shift points match yours. When the belt was off a tooth I couldn't shift at low rpms and get in to the high gears as fast. Word to any VX owners who aren't getting this kind of performance, it may be your belt. I've also noted that I can cruise up hills in a higher gear without lag and that my shift point has dropped from about 1700rpm to 1200rpm. Also when I cruise 60mph the rpms were at 2200 and now they are a smidge under 2000. Overall changing the belt position has made the car have better throttle response, lower shift points and better hill climbing ability.