91 LX Cut-Out when Accelerating

[sick6sect]

Problem: My 91' Honda Accord LX cuts out (boggs) when I press the accelerator more than 1/4 of the way (Between all gears). Noticed that it performs better when the car is cold or when I am almost on E.

This is my first Honda, let alone my first tuner. I am looking to make this a reliable daily driver, and race my Cutlass. I purchased this vehicle from an independent car seller about a month ago and all seemed great until my first fuel up (Drained tank and added Sea Foam). I also changed the oil, spark plugs, wires, and air filter. The problem persited so I continued with what I percieved to be the usual suspects: Fuel pump, fuel filter (replaced the filter and ran a pressure test). The fuel pump checked out, so I checked the Oxygen Sensor and the IAC. Both of these showed problems, but I cannot afford them until next paycheck. I will update with any progress, or lack there of, when I complete the new repairs.

Maybe its the Distributor?

I have searched the forums for some time and have discovered numerous reasons for the car to act this way. Please let me know if I am on the right track.

[Jorgian]

Problem: My 91' Honda Accord LX cuts out (boggs) when I press the accelerator more than 1/4 of the way (Between all gears). Noticed that it performs better when the car is cold or when I am almost on E.

This is my first Honda, let alone my first tuner. I am looking to make this a reliable daily driver, and race my Cutlass. I purchased this vehicle from an independent car seller about a month ago and all seemed great until my first fuel up (Drained tank and added Sea Foam). I also changed the oil, spark plugs, wires, and air filter. The problem persited so I continued with what I percieved to be the usual suspects: Fuel pump, fuel filter (replaced the filter and ran a pressure test). The fuel pump checked out, so I checked the Oxygen Sensor and the IAC. Both of these showed problems, but I cannot afford them until next paycheck. I will update with any progress, or lack there of, when I complete the new repairs.

Maybe its the Distributor?

I have searched the forums for some time and have discovered numerous reasons for the car to act this way. Please let me know if I am on the right track.

Replace Your Ignitor (little chip in your distributor) And Main Relay (under your dash).

[sum123]

Problem: My 91' Honda Accord LX cuts out (boggs) when I press the accelerator more than 1/4 of the way (Between all gears). Noticed that it performs better when the car is cold or when I am almost on E.

My 93 CB7 190k exhibited these exact symptoms and it turned out to be the O2 sensor that had failed without throwing a code. It took me over a month to find the trouble, but I eventually spent about $55 for a new Denso one at Advance Auto and installed it myself. Car runs fine afterwards. Other than the new sensor and a fuel filter, I didn't throw money at the problem. Don't replace the main relay trying to solve a driveability problem like this. That's just putting money down the drain. I thought it was my distributor too, so I metered everything in it that I could. All the voltages checked out fine. Later I realized the ignition system wasn't missing, but the intake system was choking on the bad air-fuel mix that was caused by the worn out old O2 sensor sending bad information to the ECU.

When you shut off a properly tuned CB7 after a drive, the engine should come to an instant dead stop. If your engine chugs on for a second or so after you turn the key off, put your O2 sensor at the top of the list for replacement. That chugging, diesling behaviour after turning the key off was another symptom on mine. After fixing the problem I realized that at those moments it was almost like the intake was blowing out the last bit of bad mix after I turned the key off, but that same chugging thing had been happening much faster as I bogged and limped up and down the road in my sick CB7 trying to figure out what the hell was wrong with it. O2 sensor.

[sick6sect]

My 93 CB7 190k exhibited these exact symptoms and it turned out to be the O2 sensor that had failed without throwing a code. It took me over a month to find the trouble, but I eventually spent about $55 for a new Denso one at Advance Auto and installed it myself. Car runs fine afterwards. Other than the new sensor and a fuel filter, I didn't throw money at the problem. Don't replace the main relay trying to solve a driveability problem like this. That's just putting money down the drain. I thought it was my distributor too, so I metered everything in it that I could. All the voltages checked out fine. Later I realized the ignition system wasn't missing, but the intake system was choking on the bad air-fuel mix that was caused by the worn out old O2 sensor sending bad information to the ECU.

When you shut off a properly tuned CB7 after a drive, the engine should come to an instant dead stop. If your engine chugs on for a second or so after you turn the key off, put your O2 sensor at the top of the list for replacement. That chugging, diesling behaviour after turning the key off was another symptom on mine. After fixing the problem I realized that at those moments it was almost like the intake was blowing out the last bit of bad mix after I turned the key off, but that same chugging thing had been happening much faster as I bogged and limped up and down the road in my sick CB7 trying to figure out what the hell was wrong with it. O2 sensor.

I'm have not noticed a problem with the car dieseling. I was able to drive to work this morning (15 miles) with little problems from the car (around 35° outside), but it appears my thermostat works when it wants to now. Also drove the car last night with the IAC unhooked, I noticed some improvement but not enough to keep it unplugged (check engine light was annoying).

[sum123]

It's rare for an IACV to fail but perhaps yours is really broken. Did you check the ohms on it yet?

While my car was messed up, I had a few days where I thought the bogging problem was gone and the engine seemed to be running okay, but still a tad rough. The real test is the short drives. Try warming up your car and driving a few miles to the store one cool evening. Turn the car off and leave it off about 10-15 minutes, then start it up and take off. If your O2 is bad, this is when the engine will start bogging. At lease it was like that with mine.

The IACV is a part that rarely fails, but it is a hardworking electromechanical device. I guess it's possible yours is bad or going bad. Did you check the ohms on it yet? Pull the electrical connector off of it and touch the pins on the valve with multimeter probes with the meter set for ohms. You should get between 8 and 15 ohms. Then touch each of the pins of the IACV with the positive probe while touching the other probe to a ground. There should be NO continuity of current between either pin and the ground. If done properly, the meter should show no reaction. If it does react, your IACV needs replacing. Also with the key on but engine not running use both probes to check for voltage on the wire coming from the car that connects to the IACV. That wire should show voltage.

[cloudasc]

To check whether its the o2 sensor, you can just unplug it, yes it will turn on your check engine light, but just drive it around and if the problem still persists you know its not the o2 sensor, because the car is running off its "basemaps"

[sum123]

While I was trying to figure out what was wrong I had a shop that does free estimates inspect my catalytic converter. The let me come in the bay and look at it. I was right there at the o2 sensor but never even thought about it. Too busy thinking that part would throw a code if it was faulty. Good thing is its' an old car with one o2 that was fairly cheap to replace.

[sick6sect]

It's rare for an IACV to fail but perhaps yours is really broken. Did you check the ohms on it yet?

While my car was messed up, I had a few days where I thought the bogging problem was gone and the engine seemed to be running okay, but still a tad rough. The real test is the short drives. Try warming up your car and driving a few miles to the store one cool evening. Turn the car off and leave it off about 10-15 minutes, then start it up and take off. If your O2 is bad, this is when the engine will start bogging. At lease it was like that with mine.

The IACV is a part that rarely fails, but it is a hardworking electromechanical device. I guess it's possible yours is bad or going bad. Did you check the ohms on it yet? Pull the electrical connector off of it and touch the pins on the valve with multimeter probes with the meter set for ohms. You should get between 8 and 15 ohms. Then touch each of the pins of the IACV with the positive probe while touching the other probe to a ground. There should be NO continuity of current between either pin and the ground. If done properly, the meter should show no reaction. If it does react, your IACV needs replacing. Also with the key on but engine not running use both probes to check for voltage on the wire coming from the car that connects to the IACV. That wire should show voltage.

I checked both the IAC and the O2. With the IAC I am getting no Ω reading at all and there is no continuity. (Apparently it's half broken) The O2 sensor failed the tests. And problem occurs some of the time when restarting the vehicle. I wish the problem was constant (would be easier to notice any changes.) Will buy the O2 when I get paid.

[sum123]

I had to check my IAC a few times on a few ohm dial positions on my multimeter before finally seeing about 13 ohms consistently. I can't remember where I set it but I think it was the 200 or 2000 position, but it might have been the 20k position. Don't touch the pins at the same time. Touch one, hold it there then touch the other one. Touch lightly and keep the pins still. Measuring Voltage is a piece of cake. Measuring Resistance is more tedious and takes patience.

One reason I checked the Cat is after a few weeks of trouble I began to pay attention to what the bogging really felt like and noticed that I could feel it under the cabin. It was the improper air-fuel mix belching out of the exhaust manifold and on through the Cat and pipes under there. Each bog was a big bubble of stuff that had been half-ass burned. I still didn't suspect the o2 sensor, though. I had read that a bad o2 makes the engine run hot, but my temp gauge stayed at normal. Still the engine seemed hot and smelled hot when I would pop the hood after a bogging session. That was heat from a combination of rich/lean running. Car is running very smooth right now and has good power, but it remains to be seen if I've got other damage from continuing to drive the car for weeks with it bogging down a couple of times a day.

I'm going to be preaching o2 sensor to CB7 owners for a long time.

[MrSpeedy]

Problem: My 91' Honda Accord LX cuts out (boggs) when I press the accelerator more than 1/4 of the way (Between all gears). Noticed that it performs better when the car is cold or when I am almost on E.

This is my first Honda, let alone my first tuner. I am looking to make this a reliable daily driver, and race my Cutlass. I purchased this vehicle from an independent car seller about a month ago and all seemed great until my first fuel up (Drained tank and added Sea Foam). I also changed the oil, spark plugs, wires, and air filter. The problem persited so I continued with what I percieved to be the usual suspects: Fuel pump, fuel filter (replaced the filter and ran a pressure test). The fuel pump checked out, so I checked the Oxygen Sensor and the IAC. Both of these showed problems, but I cannot afford them until next paycheck. I will update with any progress, or lack there of, when I complete the new repairs.

Maybe its the Distributor?

I have searched the forums for some time and have discovered numerous reasons for the car to act this way. Please let me know if I am on the right track.

If you are short on money, you may wanna do this. Take your dist.cap off and the rotor. Check the metal pins inside the distributor cap if they are all white, rusted or just dirty. Scrape those with a screwdriver and you can also put some rust off spray on them. Also do this same to your rotors metal head. While you've got the dist. cap off, check if you've got some of those 4 wires loose on the ignitor. They come off just pulling them, but they should be snug. Tighten them if needed. Put all back together and make a test drive. Might be that it doesn't solve the problem if you've also got other problems, but it is free and it doesn't hurt you either.

Don't want to be an ass, but I hate it when people are telling you to buy new parts, even though you aren't exactly sure what's the problem. My opinion is that you should narrow your symptoms to a specific problem (not always possible) and THEN buy the stuff you need. Not the other way that you narrow the problem with buying new parts. Ofcourse you will find the problem when replacing all the parts.

[sick6sect]

I just cleaned out my IACv, it was about a 2$ fix. I retested the Ω, continuity, and voltage. They all ckecked ok, but the Ω's read at about 11. The test drive did not reveal any improvements, seemed hard to start with a rough idle. Now I'm waiting to get paid, O2 sensor at very top of list now.

[CBSeven...SR]

I just cleaned out my IACv, it was about a 2$ fix. I retested the Ω, continuity, and voltage. They all ckecked ok, but the Ω's read at about 11. The test drive did not reveal any improvements, seemed hard to start with a rough idle. Now I'm waiting to get paid, O2 sensor at very top of list now.

Yeah you might want to check your o2 sensors and clean out your throttle body and intake manifold might also be he problem?

[sum123]

I just cleaned out my IACv, it was about a 2$ fix. I retested the Ω, continuity, and voltage. They all ckecked ok, but the Ω's read at about 11. The test drive did not reveal any improvements, seemed hard to start with a rough idle. Now I'm waiting to get paid, O2 sensor at very top of list now.

You just want those ohms to be within spec, and yours are. Difference in outdoor air temperature might have made it a bit lower. Replacing the O2 sensor will probably get you straight. If you turned the idle screw while diagnosing the trouble, you'll need to reset the idle after replacing O2. The IACV can make adjustments but it cannot compensate for that idle screw being too loose or tight.

[sick6sect]

IACv back on the list. I had to stop a few times on the way home from work and noticed my idle jumps (700 - 3000) when I park after a short drive. After my second stop I decided to unplug it. The idle immediatley dropped to about 750, and I noticed an improvement on how the car drives (at least for 5 miles). The car then resumed it's cut-out action upon acceleration. I am led to believe the problem may be a mixture of the IACv and the O2 Sensor. Will replace both to eliminate any doubt. Payday is Monday

[sum123]

Your IACV is likely fine. It's just trying to figure out what the heck is going on while the faulty o2 continues to send bad data to the ECU which in turn is telling the IACV to do jumping jacks to try to get the right amount of air to mix with the fuel. The IACV is just following instructions from the system. Meanwhile, the cylinders are saying "heeeey, we don't mind idling, but what the heck is this junk you're asking us to burn in order haul this 3,000 pound car down the road? Sorry, NO CAN DO!" The result is bog, bog, bog. You've probably noticed that the bogging and the strange idle go hand in hand. I got to the point I could predict the bogging just by noticing the idle bouncing or noticing that the idle felt kind of weak. Even at idle a little barely noticible bog is there. That becomes a huge bog under load.