94 honda civic vx issues
 

last month i was driving a 1997 buick park avenue gas hog with bout 171k miles on it and i missed my civics too much and managed to trade it for an unmolested other than riding on steelies 94 honda civic vx and it just hit 130k miles on it.

its got quite a few issues with it of course some i know of others i dont.but i really wanna get this fixed up and be able to get that beastly mpg with it. while driving and shifting in between gears the rpms most of the time will stay high and i shift at bout 3k rpms.they will most of the time stick and take a while to drop and/or they will drop and reach almost 0, the car shutters a little then they come back up.once in a blue moon the car will stall from it. this is one of the biggest issues im having and am not sure where the cause could be at if its the IACV or the TPS or something else im unaware of.

the plug wires i believe do need replaced they have a little orange powdery residue at the tips but im not positive if this wud fix that issue.also while driving at lower rpms the it has slight hesitation thats why i also suspected the wires.But the previous owner was telling me about a tube underneath the intake manifold thats used during lean burn mode that probably collapsed but i cant find anything about this part online.

While shifting it doesnt grind at all but sometimes in gears when accelerating i will hear a grinding noise and from what iv been told its a throw-out bearing. the battery went out at one point and got that replaced.

i had to have the slave cylinder in the clutch replaced since it leaked all the way dry while driving and i cudnt shift it so got it towed to a shop cuz i had no other choice since i had no idea what was wrong with it. this shop is crazy and definetely never taking it there again. the first time they said they did a diagnostic on it and said it was fine after the clutch was worked on.

i drove it and it still had the same issues.i was questioning whether the tech even test drove it around the parking lot. took it back in they said the radiator had a leak on the bottom and wanted 400 to fix it.forget that im just gunna replace it myself radiator is easily under 100 bucks. then they said that they cleaned out the iacv and put it back on and the car was still having the bad idle problem so they quoted 400 to replace that. again screw that i cud buy a new one for 120 or so and just put it on myself i know about that.

this seems like a lot but to sum it up im curious if these sound like easy fixes and its worth fixing up. if the idling issue cud be something unrelated that i dont know of. also curious if an iacv from an 89 crx dx would work with it one of my buddies has one and i havnt tried that out yet. any advice would be much appreciated im still in the process of learning and fixing up hondas and enjoy it a lot

Paragraphs please.

At 3,000 RPM your engine should sound like it's screaming and that something is wrong... a stock VX just doesn't sound right or happy with the engine going that fast, your gas mileage will also suck.

It sounds like the tube under the intake manifold that you are talking about is the PCV tube, that has a grommet that often drys out after 20 years and allows extra air in the engine, most of the time it just causes idle bounce, but if it's in poor enough shape that it's collapsed then it might also have a big hole ripped in it, or be gone all together.

Wud this tube be something i cud easily replace by lifting the car up jacks and getting under there? He did say it was a cheap part at autozone. it does start screamig at about 3k rpms.vtec-e works just fine.i was actually wondering if a cold air intake wud be better to hear the vtec more but from what iv read its best to keep the stock air intake and filter on there. Just when shifting the rpms have actually started to raise just a few lines then start dropping slowly.and i know that when shifting inbetween gears or neutral the rpms r supposed to drop down to normal idle. And yes gas milage is barely hitn 30mpg and that sucks for the vx

Why are you revving the engine up to 3,000RPM??? even merging in to traffic on the freeway it's rare to need to rev the engine up that high.

http://www.hondaautomotiveparts.com/...3sr301_e08.png

#4 is the tube I'm talking about and most part stores do not sell it, a Honda dealer might charge you $15 for it or Honda Automotive Parts sell it for $7 and a few bucks for shipping, if you order that tube get part #3 as well, you can not get to that tube by jacking the car up, you need to find someone with small hands, to get the grommet (#3) out you need needle nose vise grips.

A cold air intake will let you hear the engine more because it will de-tune the air intake and make the engine louder/rougher/rattle, I don't know of any positive effects that it could have.

I should most definitely correct myself on that one. ima watch myself again while driving.when i drove the 89 crx i shifted at about there.in the vx its lower. my next step is definetely to replace that tube and definetely figure out the issue with the rpms sticking or dropping to 0

also is it a pcv valve? im trying to find one on ebay if its cheap enough

Not everyone has found a PCV valve but some do... if there is a valve is in the lower part, not up top where you can get to it easily.

shifting when the shift light comes on is the best rule, otherwise shift before the engine starts to scream! 3k RPM is crazy! 2k RPM makes me twitchy and you have plenty of power at that speed!

So if you find a PCV valve then clean it out and you can get a replacement at the auto part store for a few bucks, but if you don't find a valve then don't panic, just make sure that the hose is in good shape and that the #3 grommet is soft and sealing well.

The VX uses the same bearings as any other Honda engine. Due to the restrictive intake manifold it stops building power at 5500rpm which is probably why the redline is only 6000, but it's 99% part compatible with engines that rev up to almost 8k. You're not going to break anything rev'ing it up to 3k, but you will hurt your economy.

I once destroyed a distributor in a B series motor rev'ing it past 9k (in 5th gear) but it sustained no other injuries.

yeahh i totally forgot about the shifting light. when it works. cuz it doesnt work 100% of the time ill shift to it. sometimes i just like to drive a lil zippy nothing too extreme. and i noticed that too. after i got it i noticed it redlined at 6k and wont go past that at all. but not something to experiment with since its a vx. so after i figure out all these issues with it. definetely want to find a cold air intake that will fit it.
also out of curiousity.dont get too hard on me about it because it definetely would not be a permanent mod. down the road after all these issues are fixed, if i wanted to have a lil fun with it and possibly throw on a 4in apexi n1 muffler on it but still keep the stock exhaust to put back on when i want to sell. how much of a difference in mpg wud that affect the car? personally i just really cant stand driving quiet cars.especially manuals.i would leave everything else stock.

You might see a MPG loss by swapping to a larger pipe, and probably no power gains either with the stock intake manifold being the limiting factor. A new muffler would be entirely "cosmetic".

Understandable.i dont care bout more hp.how big of a mpg loss we talkn bout?

I don't have a VX and I don't have a before and after of my car either - when I got it, it had a 3inch pipe and an obnoxious muffler and I've been too cheap to replace it. Couldn't give you any numbers.

Whatever the losses are though, it's not from backpressure as is commonly thought but actually quite the opposite. The stock system is tuned to maximize "scavenging" which to my understanding is when the exhaust pulse of one cylinder travels down the pipe and causes negative pressure exactly when the valves open up on the next cylinder to fire, and actually pulls the exhaust out.

It seems the ideal pipe size is "just big enough" because it maximizes scavenging without restricting.

Understandable.im not even if throwing the muffler im looking at on it would even give it much more sound.on my previous 89 crx with a stock d15b2 engine i put a cheap ebay 4in muffler on it and supprisingly it sounded really nice.then i had the cat converter taken off and a high flow cat converter straight pipe put on that was really cheap too and it sounded even better.idk driving a quiet stick shift really gets to me haha.and if throwing on an apexi n1 4in muffler on it gives it descent sound and i can still have high mpgs then id enjoy the hell outa this car

I'm on my 2nd VX and my brother owns a VX and something I've noticed is that they do not like after market over sized exhaust, that for whatever reason it leads to an early 02 sensor death and on a VX that is a $200 to $350 part that keeps getting more expensive! keep a good stock exhaust on the car and your o2 sensor should last 200,000+ miles, over sized exhaust like I had for a while and the o2 sensor lasted around 10,000 miles! fixed the exhaust and replaced the sensor and it's been going strong for around 80,000 miles in one car and 40,000 in my other, when someone says they were shocked that an o2 sensor was going to cost them $350 from the parts store they are shocked when I ask them if they have a loud exhaust, I've also seen a 2-3mpg increase in mileage switching to stock exhaust.

If your shift light is not working it might be from being heavy on the gas pedal, pushing on the gas tends to push it out of the peramitors that tell the shift light to turn on.

Alright.well my idea of putting a larger muffler on can be completely thrown out the window at this pt and im ok with that. Wut about the air intake on it now? Wud it hurt at all putting an aftermarket one on?

I would think it would be a bad idea on vehicles that use a MAF sensor, but your and my Honda have MAP sensors. A cold air intake will give you a bit more power and a bit less economy, while a warm air intake should do exactly the opposite.

You should get more opinions on the other effects, I'm not terribly knowledgeable on the subject beyond what I've said.

If you want to make a new intake then get some books on intake design, but if you do the math in them for the perfect intake size you will most likely end up with something about the same size as what you have now, going larger will hurt your mileage, getting rid of the chamber that is under the air filter in the bumper will also hurt your mileage and make your car louder, warmer air will help your mileage colder air will hurt your mileage.

dang. well iv made up my decision to leave this thing stock. my next question is out of curiosity but what about GFchips.com. would this really positively effect the vx much more?

From GFchips.com:

The factory ECU already does this in all cars, and the VX does it better than most cars in part because it uses a very sensitive O2 sensor - hence the $300 replacement costs. The VX's lean burn intentionally leans out to 18-22:1 under low load conditions (lean burn) to save you even more fuel.

Honda has tuned the system such that it doesn't burn any valves when running these super-lean AFRs.

Advancing ignition timing can also be achieved in your car by loosening the bolts on the distributor and advancing (turning it toward the firewall) ~2 degrees. This should probably be done with a timing light (and not done lightly), as advancing too far can have some pretty serious consequences (such as a blown motor), hence Honda shipping them from the factory with somewhat conservative settings.

That said, your car is an extremely fine-tuned machine from the factory and almost any aftermarket modification to it will just make it worse.

EDIT: If you want a mod that will improve gas mileage and improve your car cosmetically at the same time, I'd suggest lowering it ~2".

I lowered my first vx and didn't see any improvement in mileage the lowering suspension did however cause a rougher ride and seemed to wear out other parts of my suspension causing me to replace the spend about $600 putting it back to stock height, LRR tires do help, 45 to 50psi in the tires helps too, my next plan is light weight smooth wheels like the first generation Honda Insight used, there are a bunch of low rolling resistance tires in 14" sizes that would fit at that point where there are very few 13" options.
Other things that work:
Changing your transmission fluid (it takes motor oil or Honda MTF, NOT GL5 GEAR OIL, unless you like replacing transmissions!) I tend to use 0w30 synthetic motor oil in both the transmission and engine, it makes the transmission shift super smoothly and helps the engine with cold starting.
NGK v-power spark plugs are OEM and $10 for a set, they also work great, much better then expensive spark plugs, I have sets of 4 different brands of "high end" spark plugs that made my VX run poorly, the worst were the Bosch +4 and the Pulstar pulse plugs.

Thats my plan.synthetic oil change.ngk performance wires and plugs
and yeah most definetely not going to lower it. i read the same thing to online sumwhere some guy lowered it even just a little and everything started screwing up.the previous owner had a really nice set of tires on it before but wanted extra for them. but i really wanted to trade my 97 buick for it. so worth it in the long run especially got gas.

what are some signs of the head needing shaved down or something.iv looked inside the spark plug tubes(im very new to engine work only replaced spark plugs, wires and valve cover gasket before) and they dont seem as smooth as my d15b2 was. i remember hearing something about sending the head to a machine shop and them resurfacing it or something. how exactly does that work? i was also looking to see if i cud find a cheap head replacement and cant find one ANYWHERE

oh yeah. i payed attention to my driving and realized i was shifting somewhat high. also noticed that definetely in lean burn mode the car hesitates pretty bad.def gunna look for that pcv valve

shaving the head is a step below a full engine rebuild, $1,000 to have someone else do it is my guess, you can get a whole engine used and have someone install it for $1,000, so I don't think it's worth it at all! you would get your head shaved if you race and over heated your engine, if you ran it dry on coolant, or if you otherwise drive really hard all the time for 50,000 miles or more! you shave the head if it's warped, your engine is already a high compression engine.

ouch. definetely dont wanna go through all that. tommorrow i am definetely gunna do a synthetic oil change and from checking online it looks like autozone carries the PCV valve for 3 bucks so since I have the day off I am going to try and tackle it. I've taken a couple of good looks out on the car and still having trouble finding the valve location even with the diagram. its probably just me though and i need to look at it more closely

when you are looking at the engine, the first half of the PCV hose is this.

https://encrypted-tbn2.gstatic.com/i...9XCE5IqTO3MERA

it's a mess in there, but here is another view.https://encrypted-tbn0.gstatic.com/i...wT5c34ZCQPEL7k

And that is where most people think the valve is, but is on the underside of the intake manifold! right here... see that little white bit of plastic way down there? the one you have might be blue or black and dirty.

https://encrypted-tbn3.gstatic.com/i...FffXqdzcf4Bwwi

you have to get to it from the drivers side of the engine compartment, with your long skinny arm, reach under the intake manifold till nearly your whole arm is in there, you will scrape your hand and arm up and everything is hard to see, if that is not the case either your arm is really skinny or you have the wrong part.

Very helpful.the top two pics now i know where that tube is at.so the part at the end of the tube is the pcv valve? Im kinda confused about the second pic and what exactly im looking at

just fallow the hose under the aluminum intake until you get to where it enters a tin box, replace the grommet too as that is often the source of the problems with poor idle or the engine running faster then it should.

alrighty. well ill have to look around locally see if i can find the pcv valve and grommet. none of the autozones around here carry it. im actually in the middle of an oil change right now letting the oil drain out. i decided to take another look at the IACV. the shop said they cleaned it out. i dont see how they did because the two parts where the hoses connect to the valve are beyond stuck on there and definetely look aged on there. HOPEFULLY when i get this thing off and do a more thourough cleaning of it my major idle problems will be fixed. also cleaned out the throttle plate which was quite dirty. i think i see what your talking about with the tin box. thankgod im skinny as hell to be able to reach in there.

wow. sooo i just managed to get the two tubes off from the iacv. is there supposed to be fluid in the tubes? when i got each tube off a bunch of fluid idk what it is came off. i thought it was supposed to be a vacuum line going thru the valve?

Having the head shaved is no where near that involved a process. If you can do a timing belt change and a head gasket, then the only additional step needed is taking the head to a machine shop to have it inspected, cleaned, flow tested, and milled true for $75-100 out the door.

Basic process:
Unhook battery
Drain coolant
Unhook intake/exhaust manifolds
Remove valve cover
Remove timing cover
Remove timing belt
Remove head
Take head to shop.

Less than 2hrs work on most Hondas.

i just finished the oil change and let the car run sounds a lottttttttttt better. i never understand why people still use conventional oil. i always notice a huge performance and sound difference with synthetic.

i also cleaned out the iacv with carb cleaner first then a little brake cleaner. let it dry and put it back in. while driving i noticed that the rpms dont stick as hard and generally come down more. i noticed the idle though stays right by the mark at 0 rpms. it stays really low is this generally normal?

i think i saw the tin box you were talking about the pcv valve/grommet was connected to. i think i see the grommet.still dont see the pcv valve itself. called my local honda dealership and talked to someone in parts who had never heard of the vx model. he couldnt locate the part. the part he was quoting me for was like 149 bucks.

would bad plug wires cause the hesitation at low rpms? 2 paychecks down the road im going to replace the wires with ngk wires and the plugs with ngk as well.the reason i asked about work on the head is because the insides of the spark plug tubes seem worn and in cylinder 2 it is mildly rusted.just clean it out and it will be fine?

also curious about the transmission. it makes a slight grinding noise all the time in neutral.but when the clutch is engaged it stops. the worst is in first and it sounds like the grinding is stretching, if that makes any sence.it also does it in other gears slightly. from what iv read online it sounds likea throwout bearing.is this something i could easily fix?(no experience on transmissions) or should it be best to take it to a transmission shop.

In my planning for a DIY transmission swap (I also have no experience) here are a few videos I found that will walk you through parts of the process. I'm using them to give myself a visual sense of what you can expect. I think a patient person with good intelligence and the time could do the job, probably without error, if you seek and absolutely follow good direction, even when you don't fully know why it should be followed (such as replacing seals and washers even when they "look fine"). Three useful videos: one, two, three. These are sixth gen civics and your 1994 is fifth gen, but much of the hardware is about the same, if not exactly the same... so I hope this is useful. Good luck!!

these videos should help out a lot thank you. if only my internet here wasnt so slow I could check them out.

A lot of people are afraid of doing a timing belt change and if you do an engine swap you can do that for $150 for a used engine if you do the work your self as well!

Unless there is oil in the coolant or coolant in the oil I wouldn't bother pulling the head.

I've swapped transmissions twice, if it's grinding without your foot on the clutch pedal then the most common is the main bearing, if it's grinding with your foot on the clutch then it's the throw out bearing.
First time I did a transmission it took about 6-7 hours using just a floor jack and jack stands, getting the new transmission in I needed help for 10 minutes.
I ended up replacing the seals around the axles before installing the new transmission, the boot around the shift shaft is nice to replace as well but not always possible, it's logical to replace the clutch with a stock style clutch, not a race clutch unless you never drive in town or stop and go traffic and for installing the new transmission, take it to a car wash first and pressure wash it, keeps the dirt from falling in your eyes.
If the grinding is not real bad, try replacing the transmission oil with 10W30 or 10W40 instead of 0W30, the extra thickness can prolong the bearing life.
If you want to replace the bearing your self it's a $20 or so part but I found both my transmissions for $100 and $150 and with low miles on them.

I might just do that later find a transmission for it.shoot a shop will probably charge more just to replace the bearing. and im not sure i wanna risk working on transmission yet this is my only car to use at the moment

How important is the second bolt for thr IACV? After taking it off i noticed it was only bolted on with 1 bolt the other one was not on there.right after i cleaned the valve and put it back on the idle issues seemed to go completely away.but yesterday the idle issues came back.is that second bolt really that important or cud the valve be bad?

You could test to see if there's a vacuum leak there. Unplug the IACV and start your car, let it warm up, then spray some carburetor cleaner on an around the IACV. If any air is getting in around it, you'll know.

This is what its currently doing.
https://www.youtube.com/watch?v=wCCj...e_gdata_player

I can't tell if that's you giving it gas or the car. Does it do that also when it's warmed up? I noticed that it's bone cold on the temp gauge. Check the vacuum get a gauge. It will tell you tons!!!!