Hello,

I have a 93 Accord that always has a rough idle and when the brake is pressed it is worse. Whe the car warms up it is still rough and the idle speed goes up and down between 1000 and 1500 rpms. It actully runs like like it is missing.

I took it to the emiision testing and it failed. The Hydrocarbons were too high. The limit was 25000 and my car is at 50649.

I thought it could be a vaccum leak but, I can't find it.

I have tried to spray all of the vaccum hoses with starter fluid and the idle does not smooth out.
I tightened the brake booster bolts thinking it could be loose. It did not work.
There is a sensor ( possably the TA Sensor) on the front of the PGMFI that if unplugged the idel smooths out. I replace the sensor thinking it would fix the problem but, it didn't.

Couldmy problem be the car's computer?

CAN ANY ONE HELP? I have to pass emissions by Friday.

Any ideas and pictures would be greatly appriciated!!!!

 

Sounds like you have a couple issues.

HC/ Hydrocarbons are unburned fuel btw.

have you done a tune up ever? how old is the catalytic converter on your car? any mods on your car? etc... give us more info?

 

You are probably due for an EGR port cleaning, where you drill out the ports (little skittle sized circles) on the intake manifold and clean out the runners. The parts are cheap and if you have a slide hammer the process is simple. If you do clean them, make sure you do all of them.

 

I don't have any modifications. It is all stock. I have changed the plugs, wires, oil, air filter.
When I was cleaning the car yesterday it had lots of dust stuck under the dash and floorboard and doorjams. I kind of think that the car has been under water at some point. I'm going to swith out the cars computer and see if it helps.

On the back of my emissions test it says the high HC count could be due to VAccum leak, ignition system malfunction, faulty computer controls, air injection sytem failure, incorrect engine timing, incorrect engine idle speed, improper fuel injector operation, internal engine problem, incorrect carburetor setting/adjustment
inproper/missing Cat/Converter.

I don't think that I have the skills to drill anythig out at this point.

 

Honestly this all sounds like issues steming from ignition problems... rough idle and lots of unburned fuel out the exhaust.

I would check the distributor out... start with the cap and rotor first imo.

 

I live in Colorado and had this same problem. Sounds like the same thing i had. I replaced my dist cap, rotor, wires and plugs. Changed the oil, ran a can of BG44K through it and it passed. I had an arc in one of my plug wires that was causing the car to only run on 3 cylinders, giving me the same problem that you have. Give me a shout if you need help tracking it down.......

 

If the idle gets worse with the brake pedal depressed that is usually a leaky power brake booster going bad. These need to maintain vacuum at all times. Try plugging the hose to see if the car smooths out. Also a quick way to clean up tail pipe emissions is to addd about 6 cans of isopropyl dry gas to an eighth of a tank of gas. Car will run hotter and burn more hydrocarbons- remember not to let that mixturte sit in your car too long- you need to burn up that fuel and fill up the tank.
Only use Isopropyl dry gas for this...

 

https://honda-tech.com/zerothread?id=313708

 

This is a stock car... I would address these problems correctly and fix them rather than band-aid the situation with a temp. fix.

As it is your performance is suffering, driveability as well, your wasting fuel, and failing emissions.

I would spend the money and fix it... none the less, if your emissions are anything like the crap here... you can show them the receipts for your tune up/ repairs and they will give you a waiver if it all totals enough (which varies slightly depending on the vehicle but is around few hundred bucks here... the emissions program is such a scam here.).

 

I replace the cap and rotor. It seems to run a little smoother but when the brake is pressed it gets rougher. I took the brakebooster hose off while the car was running and it gets a smooth idel then. I don't have timme today to replace the brake booster so I will try to use the BG44K and go have it retested because this is the last day I can go back to emissions for free.