I bought this to commute to school [aboot 500/week]. 168,000 miles. So far have gotten 30-40mpg driving at about 60mph, but I'm hoping to do better. Car bogs a bit at low throttle, so I replaced the stock TPS but problem persists. Also, car idle varies from 600rpm to 1300rpm when hot. Changing the load on the engine affects the idle a bit [ac on/off, wiper on/off, etc] as you would expect. I can't seem to figure out why the idle creeps up ad down. The dizzy and wires look new, but I have no idea if the previous owner had the right parts put on. Me thinks I should look at O2 sensor or ECU . Please help me if you have any clues as to what to look at next. I want to get about 50mpg or more if possible. Thanks all for making this forum so information rich!
Yes!! Someone with the same problem as mine! Ahem... I mean, sorry to hear your car has a surging idle and lags at low speed. And, umm... welcome to the forums!
Heh, my car has the trim faded like yours too. I think there was an emblem there that came off. Your FE is kinda low, tho. I drive to get passed, but I get 65mpg. At 60mph your Fuel Economy should be over 50mpg I think.
Actually, my car no longer lags or stutters at slow speed. I think the Valve adjustment and the correct spark plugs were the biggest factor for fixing this problem. Do a full tune up including spark plugs--make sure your car has the right plugs!! This is very important. Under the hood it should give you the number for the right ones. The NGK something 11 is the ones you want. Look under your hood. And change the other tuneup items, the (forget what it's called), but anyway, fuel filter, air filter and spark plug wires. Any other tune up items that might help? The other thing that helped with the lag at low RPM is a valve adjustment. Does your engine sound like jingling change when you go hard on the gas at low RPM? Best place to test this is going up a hill at 1100 1200 rpm. I think that's all I've done is the valve adjustment and the tune up. I also replaced my timing belt and alternator belt, but not sure if that would have any bearing. If you need to change the timing belt, check the alternator belt, maybe change the fuel pump while your at it, and do the valve adjustment then as it is easy access when getting to the timing belt. Make sure you check out TomO's profile -- he has some great links and info on the VX. He is kind of the VX guy on the forums.
Oh, and anything you learn about fixing the problem... please pass it on!! thanks
Edit: Umm... maybe make sure your car really is a VX. Only reason I say so, your rims don't look like the stock VX rims and your FE doesn't reflect a VX's either, but rather a normal DX or CX. But the power lag I think is unique to the VX. How much did you pay if you don't mind my asking? Car is nice shape!
My VX also hesitates at low throttle also, but the idle is pretty smooth. If it makes you feel better, when I first bought my VX I consistently got 40MPG. When I found gassavers my mileage jumped dramatically, with the only car modification being 45psi in all 4 tires. The rest of the change was driving habits, as these are much cheaper and easier then repairs . Just curious: Did you replace the TPS (and calibrate it) or did you replace the whole throttle body?
I haven't tried anything yet to try to fix the bog in my VX, as it hasn't really bothered me enough yet, though it does bother others who drive it. I was thinking TPS, too bad it didn't work out for you. My car could really use a tune-up too, and I plan on replacing the oxygen sensor. I'm sure with a few maintenance items and a little practice you will reach 50mpg+. Even with the relatively poor maintenance, I can get 60+ mpg if I have all highway (at 55mph). As you can see my 90 day average is of course less than this due to my mixed commute. Note I also don't have the VX rims, just plain ugly steels. Keep us updated on what repairs make the most difference for you.
Thanks for the good info! The title says VX, so I guess it's legit. I got a bunch of receipts with the purchase that shows someone was trying to figure out what was wrong. Its got a new timing belt and water pump, new plugs [ZFR5F-11 maybe if I'm reading it right], PCV valve, distributor and rotor, plug wires, fuel filter, valve cover gasket, outer cv boot kit, alignment and A/C rebuilt to the tune of $490. All of this in the last 18 months! One receipt says that the car was stalling and it looks like the distributor work fixed that. I think that the previous 2 owners threw money at it trying to figure it out and just gave up. The lady I got it from had it for less than a year. There is no valve clatter or rattle that I've noted and I do hills at low rpms almost daily. It's still getting better mileage than my scooby outback, but I won't be satisfied until I get more out of it. I replaced the TPS and I really couldn't see how one calibrates it. Its a piece of plastic with no discernable user tweakable parts. Not many options on the positioning of it either. I just slapped it on there. If you know of any calibration data please pass it on. I'm going to try to find some VX rims, they're lighter right?
How much you want for the rims? I've realized that I have 5 temp plugs when I need 4 temp, so that is my next thing to swap out. Prolly get to it tomorrow if the rain moves out. I'll post the results and let you all know if that fixed the bogging.
Oh yeah, I paid $1800. I was the first to look at it on the day it was listed. Well worth the 4 hour roud trip if I can get her up to specs.
As far as calibration, I ran across this thread here which describes calibrating it with a volt-o-meter. Since Honda doesn't sell the TPS by itself (only as a throttle body assembly) they assume you wouldn't have to do this, so it isn't in a manual as far as I know.