History of my 92 VX troubles (and help request)
 

History of my 92 VX troubles.

First off the guy that I got the car from totaled it (front passenger side) bought it back from the insurance company and Tried to put it back together. He did an OK job but due to PA DOT being dicks he failed when he sent in his application for a Salvage Title. It sat in his mother?s yard for about 1 ? years before I bought it.

It had about 174,000 miles on it.

When I got it ran terrible due to the old gas in it. I topped the tank off with super.

Once that tank was gone I replaced the front strut that was fubar. Seafoamed it, Changed the oil and filter, air filter, Battery, Distributor cap and rotor, brakes, Alternator (that lit on fire), plugs and wires. I ran Chevron Tecron twice and ran the Honda fuel service spray in the intake twice. I took the idle control valve off and cleaned it. I also checked the timing.

I did get a CEL 48 and 17. When doing the trouble shooting as per Haynes Manual they came out as ?intermittent? and don?t worry about it. I replaced the o2 sensor with a genuine Honda part and since have not seen any CEL?s nor have I seen any improvement.

Here is my problem as you can see by my gas log I get crappy mileage even with conservative driving. I drive this similar to my CRX that it replaced and I was getting almost 50 MPG on that. It idles terrible at best it jumps from 1000 rpm to 1600 and back about every 3 to 5 seconds. The other problem I have is that at certain points in the throttle I actually bog down and loose some power when pushing in the gas peddle (normally just a bit it is not like I am flooring it) I have to really push in the gas to ?get past? that or let the gas out totally and try again. Similarly if I bump start in 3rd gear at say 35 mph on a slight upgrade and hit the gas it will bog down sometime bog down a lot.

On my list of soon to do?s are:

Hook up the DMM to monitor lean burn to see if that is working.
Pull out Idle Control Valve and clean it again.

If anyone has any other suggestions please let me know. I have become totally frustrated with this car. I bought it with full expectation of improving on my 50 mpg from my CRX by 10 mpg not loosing 10.

Thanks in advance for the help,

Jack

Idle issues can be caused by a vacuum leak, so I'd check all of your vacuum lines and replace them if need be. Cars this old can have this problem, especially if it was not being used.

I would also check your TPS sensor, as it may need to be replaced. I can get you one for cheap, unlike Honda which does not sell this part by itself (they expect you to buy a new throttle body, which is less than cost-effective).

My money is on a vacuum leak, however. A good way to check is to get some starter fluid and spray it around the vacuum hoses while the car is running. if the idle surges in a particular spot, that is where your vacuum leak is.

Once you have tried these things, we'll know where to go from there.

BTW, an alternator catching fire is kind of scary!

My car bogged the way you described when I had my vacuum leak. It also caused a rich condition (the leaking hose was to the MAP sensor), and mileage plummeted (could see it on the SG1). The spark plugs were black with soot within half an hour of running it like this - though it was an extreme leak.

Just FYI.

Hope you figger it out.

Ok I will give that a try and let you know how it goes.

Ya lucky for me I was still there after I reconnected the battery or I would have burned that baby down.

TPS Sensor is a great place to start, let me know if you need the offical Honda procedure for tesing it. I have the Helms in PDF format and can send it to you. The other things to check out are the timing (both the distributor and cam timing) Distributor timing should be set at 16 deg BTDC. Also, the code 17 is for the VSS... Check the electrical connection on the sensor for corrosion and to make sure that the VSS is fully seated and getting the proper voltage and ground. Also make sure that there is sufficient grounding in the engine bay. You should have the ground from the battery to the shock tower, one from the transmission to the chassis, and one from the head to teh chassis near the drivers headlight. Also check to make sure the wire harness is grounded at the thermostat housing on the back side of the motor. Make sure that you have the proper spark plugs in there. They're not the same as the other honda plugs. They are a BRK4RF-11 IIRC, the main thing is they are a heat range of 4 not the 5 that other honda motors run. I had the same bogging problems when I bought my VX because of the 5 heat range plugs were in the car. Check your compression numbers as well and post those up. Cleaning the EGR system with carb cleaner or even EASY OFF oven cleaner will help things as well.

Try those things and get back to me. Also, check your ECU (in the passenger kick pane) and make sure it's a P07 (just somethings to make sure that you have the proper ECU running the car).

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

https://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 forgot to also add: Check to make sure that none of your brakes are hanging up. Easiest way to check is to go for a drive that involves some braking. When you get to your destination, use your hand or a infrared thermometer to check the tempurature of each wheel. The fronts should be the same temp and the rears should be the same temp. If you have one wheel that is a lot warmer than the other, that is your hanging brake. This also works to find out if you have a caliper that is seized open as it will have quite a bit lower temp.

Jeez I had to print that so I could figure it all out. Ok here are my answers

PDF Helm... I have one (I think it is the one eveyone has not chaptered in anyway) It has the big "smudge" on the first page. I downloaded that before I even picked up the car.

Grounding I replaced the ground wire that attaches near the driver headlight. I will check the rest.

I did put in the "vx" plugs.

I am pulling out the ECU this weekend to hook up the lean burn monitor and will double check it is a P07.

The VSS I did the trouble shoot on that as per Helm's and it was ok (or intermitant). I only got that code once and it never came back.

EGR system (do you mean valve?)

I will get the compression numbers and do the TPS trouble shoot.

Thanks,

Jack

Ok no vaccum leak. Or at least not one that sucked in any of 1 and 1/2 cans of starting fluid.

How much do you want for the TPS? If it is cheap enough I will just toss in a new one.

Thanks,

Jack

Sorry, Jack, when I get going on diagnostics I can get long winded.

Ok that is great that you got all that other stuff checked so that stuff is out of the way.

EGR System, yup, I meant clean the whole EGR system. The Valve, and the ports (as best you can) unless you get the EGR kit from Honda. With taht kit, you can remove the aluminum "lumps" in the intake manifold and clean the EGR passages. Otherwise you can try to spray carb cleaner into the ports as best you can and drive the car around. The manifold vacuum will be enough to pull the carb cleaner through the ports if they aren't totally clogged.

I'll keep this one short so you don't have to print it out :o

Looking forward to your compression numbers as I need to do the same test on my VX motor that has about 316K miles on it now.

PS- be sure to do that brake check that I added up a couple posts as well. It's always good to get teh easy things out of the way.