Misfire with my 91 Accord EX

[Steve (25)]

Recently, my 91 accord EX, when it is warmed up, started sputtering when I press the gas pedal very slightly. I.E. when I am going through a parking lot under 20 KM per hour. If I accelerate more aggressively but not excessively, everything is great. All other times it appears to be normal, just when starting off with a gentle foot. This has been happening for about 1 month.

New Parts:
Plugs
Wires
Cap and rotor
Checked air filter
Fuel tank Injector cleaner

Any advise?

Steve
Ottawa Ontario

 

[disallow]

whats the tension on your timing belt? Has it
skipped a tooth?

t

 

[jim beam]

Recently, my 91 accord EX, when it is warmed up, started sputtering when I press the gas pedal very slightly. I.E. when I am going through a parking lot under 20 KM per hour. If I accelerate more aggressively but not excessively, everything is great. All other times it appears to be normal, just when starting off with a gentle foot. This has been happening for about 1 month.

New Parts:
Plugs
Wires
Cap and rotor
Checked air filter
Fuel tank Injector cleaner

Any advise?

Steve
Ottawa Ontario

replace the thermostat with a new oem one. cured similar symptoms in my '89 civic. make sure coolant level is correct too - look in the rad, not the expansion bottle. checking the timing won't hurt either.

 

[jim beam]

Recently, my 91 accord EX, when it is warmed up, started sputtering when I press the gas pedal very slightly. I.E. when I am going through a parking lot under 20 KM per hour. If I accelerate more aggressively but not excessively, everything is great. All other times it appears to be normal, just when starting off with a gentle foot. This has been happening for about 1 month.

New Parts:
Plugs
Wires
Cap and rotor
Checked air filter
Fuel tank Injector cleaner

Any advise?

Steve
Ottawa Ontario

replace the thermostat with a new oem one. cured similar symptoms in my '89 civic. make sure coolant level is correct too - look in the rad, not the expansion bottle. checking the timing won't hurt either.

 

[motsco_ _]

Recently, my 91 accord EX, when it is warmed up, started sputtering when I press the gas pedal very slightly. I.E. when I am going through a parking lot under 20 KM per hour. If I accelerate more aggressively but not excessively, everything is great. All other times it appears to be normal, just when starting off with a gentle foot. This has been happening for about 1 month.

New Parts:
Plugs
Wires
Cap and rotor
Checked air filter
Fuel tank Injector cleaner

Any advise?

Steve
Ottawa Ontario

If you crawl around a parking lot in first, does it try to 'buck' a bit? If so you probably have a shot Throttle Position Sensor. Do a Google.com search. look under 'groups' too. Knowing your mileage would help. . .

'Curly'

 

[motsco_ _]

Recently, my 91 accord EX, when it is warmed up, started sputtering when I press the gas pedal very slightly. I.E. when I am going through a parking lot under 20 KM per hour. If I accelerate more aggressively but not excessively, everything is great. All other times it appears to be normal, just when starting off with a gentle foot. This has been happening for about 1 month.

New Parts:
Plugs
Wires
Cap and rotor
Checked air filter
Fuel tank Injector cleaner

Any advise?

Steve
Ottawa Ontario

If you crawl around a parking lot in first, does it try to 'buck' a bit? If so you probably have a shot Throttle Position Sensor. Do a Google.com search. look under 'groups' too. Knowing your mileage would help. . .

'Curly'

 

[jim beam]

If you crawl around a parking lot in first, does it try to 'buck' a bit? If so you probably have a shot Throttle Position Sensor. Do a Google.com search. look under 'groups' too. Knowing your mileage would help. . .

'Curly'

good point - check for computer codes. tps always shows up as a code if it's failing.

 

[jim beam]

If you crawl around a parking lot in first, does it try to 'buck' a bit? If so you probably have a shot Throttle Position Sensor. Do a Google.com search. look under 'groups' too. Knowing your mileage would help. . .

'Curly'

good point - check for computer codes. tps always shows up as a code if it's failing.

 

[Steve (25)]

No it doesn't buck but misses...like one plug is misfiring. As soon as you load the engine by accelerating, it works great. If I hadn't put new plugs and check the gap I would have suspected this. The car has 263,000kms and works great. It an automatic. I've reset the computer to clear any faults and there are no faults showing during the diagnosis test..

 

[Steve (25)]

No it doesn't buck but misses...like one plug is misfiring. As soon as you load the engine by accelerating, it works great. If I hadn't put new plugs and check the gap I would have suspected this. The car has 263,000kms and works great. It an automatic. I've reset the computer to clear any faults and there are no faults showing during the diagnosis test..

 

[Michael Pardee]

No it doesn't buck but misses...like one plug is misfiring. As soon as you load the engine by accelerating, it works great. If I hadn't put new plugs and check the gap I would have suspected this. The car has 263,000kms and works great. It an automatic. I've reset the computer to clear any faults and there are no faults showing during the diagnosis test..

Persistent single-cylinder misfire at low throttle (often does it at idle, too, but with fuel injection that isn't always true) makes me think of a vacuum leak first of all. In the Days Of Olde that usually meant the PCV hose or vacuum advance connection (since they typically came off a single branch of the intake manifold) but nowadays the fuel injector seat seal is suspect. A gentle squirt of carburetor cleaner around the base of each injector when the engine is idling will cause the idle speed to blip if you hit a leaky seal.

As always, use carb cleaner cautiously on a running engine - it is made to be flammable. The smallest squirt that will wet the seal is what you want.

Mike

 

[Michael Pardee]

No it doesn't buck but misses...like one plug is misfiring. As soon as you load the engine by accelerating, it works great. If I hadn't put new plugs and check the gap I would have suspected this. The car has 263,000kms and works great. It an automatic. I've reset the computer to clear any faults and there are no faults showing during the diagnosis test..

Persistent single-cylinder misfire at low throttle (often does it at idle, too, but with fuel injection that isn't always true) makes me think of a vacuum leak first of all. In the Days Of Olde that usually meant the PCV hose or vacuum advance connection (since they typically came off a single branch of the intake manifold) but nowadays the fuel injector seat seal is suspect. A gentle squirt of carburetor cleaner around the base of each injector when the engine is idling will cause the idle speed to blip if you hit a leaky seal.

As always, use carb cleaner cautiously on a running engine - it is made to be flammable. The smallest squirt that will wet the seal is what you want.

Mike

 

[Jafir Elkurd]

Is it a automatic? If so, hold your left foot on the brake, put it in drive, and with you right foot bring up the RPM. Does it miss then? Is it always at the same spot that it starts? If so, turn the engine off. Bypass the vacuum hose going to the EGR valve and try again (you'll get a check engine light this time, but don't worry about it). If it goes away, you have plugged EGR ports in your intake manifold.

 

[Jafir Elkurd]

Is it a automatic? If so, hold your left foot on the brake, put it in drive, and with you right foot bring up the RPM. Does it miss then? Is it always at the same spot that it starts? If so, turn the engine off. Bypass the vacuum hose going to the EGR valve and try again (you'll get a check engine light this time, but don't worry about it). If it goes away, you have plugged EGR ports in your intake manifold.

 

[rastapasta]

If you crawl around a parking lot in first, does it try to 'buck' a bit? If so you probably have a shot Throttle Position Sensor. Do a Google.com search. look under 'groups' too. Knowing your mileage would help. . .

'Curly'

Hey---sorry to jump in here, but this is what happens with my '92 Teg (RS I think). On low gears, it'll "buck" as you describe. Will this work on my non-VTEC engine (if this is the problem)? http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7970464271&category=33557&sspagename=WDVW thnx

 

[rastapasta]

If you crawl around a parking lot in first, does it try to 'buck' a bit? If so you probably have a shot Throttle Position Sensor. Do a Google.com search. look under 'groups' too. Knowing your mileage would help. . .

'Curly'

Hey---sorry to jump in here, but this is what happens with my '92 Teg (RS I think). On low gears, it'll "buck" as you describe. Will this work on my non-VTEC engine (if this is the problem)? http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7970464271&category=33557&sspagename=WDVW thnx

 

[SJD]

Steve wrote:

For everyone who replied, I lost all the great info. If you have any ideas on this problem please reply again.

Sorry, my HD died and I lost all the PM you sent.

Thanks

Steve

 

[SJD]

Steve wrote:

For everyone who replied, I lost all the great info. If you have any ideas on this problem please reply again.

Sorry, my HD died and I lost all the PM you sent.

Thanks

Steve

 

[SJD]

I tried the first part and yes, it is around 1200-2000 RPM then smooths out. I suspect it is the throttle position sensor or blocked EGR port. I will try this on the week-end.

Steve

 

[SJD]

I tried the first part and yes, it is around 1200-2000 RPM then smooths out. I suspect it is the throttle position sensor or blocked EGR port. I will try this on the week-end.

Steve