Engine idles but will not accelerate

Hi streatbeetz23,

The idling system seems to be malfunctioning and the throttle position sensor as well.

I would suggest cleaning the throttle body and IAC valve. You can do so by using an aerosol spray carburetor cleaner.

Hi streatbeetz23,

Carburetor cleaner is the general term used. Some are called throttle cleaners.

No, those oily black deposits are not due to a bad EGR. Even those without EGR system would have the same symptoms. Those are more likely to be caused by the PCV and blowby gases.

The throttle body is the more important area to clean. Manifold would get dirty in no time.

The scan showed a bad TPS so that is what you should be looking at regarding the stalling during acceleration.

Okay, so after i kicked myself in the face dealing with the first issue i found that i mistakenly plugged the TPS connector on the MAP and vice-versa.

man was i glad ran perfect for about a day or so that is.

so i had bad gas originally when i first came back from a deployment with a bad rear motor mount. pulled off the back of the motor to access the mount and reinstalled. incorrectly hooked up the TPS and MAP but corrected that problem.

after filling up the gas tank i got about a good ten to fifteen miles and all of a sudden the engine started to misfire.

I has new plugs, new distributor, new rotor, but same racing 10 mm plug wires, probably should change but does not show any signs of leaking. but throwing codes for all four cylinders misfiring and also P1399 which i have no idea what that is and also code P0300.

all four injectors are clicking, fuel pressure seems good, at idle you cannot tell but once the engine starts to pick up or you punch the throttle you can hear the severe hesitation.

some ideas on how to fix also how i can find a vacuum leak if there is one?

trying to so not pay for costly dealership repairs but i have came so long so far doing my own repairs just so stumped on this.

is it possible the timing belt jumped?

is it possible the TDC crankshaft sensor?

need help and some step by step with some description how to troubleshoot if possible.

Hi streatbeetz23,

P1399 = P0300. Random misfire. The vehicle is misfiring and it could be caused by
1. Spark plugs.
2. Plug Wires.
3. Distributor cap and rotor.
4. Injectors.

streatbeetz23, you just saved me. Spent a week off and on doing a head gasket swap and top-end cleanup on my 2000 Honda Accord SE 2.3L (f23a1). Mainly because I was losing fluids. It was my first head job ever so I was careful to write every step down, to not damage anything, etc. Cleaned intake and throttle body, injectors, emissions valve, etc. Replaced valve seals myself too. Changed fluids and did timing too. Pretty much tore it all down, cleaned everything (completely gunked up), replaced any gaskets I could, and put it back together (under $100 total including fluids).

All proud of myself, it was time for the moment of truth. Turned the key, pumped the gas... It ran. But way worse than before. Terrible idle, died repeatedly, kept cutting out when accelerating. I let it warm up and bled the fluid and such, then took it a mile down the road... Or should I say limped it... Finally made it back home. Tons of research and videos. Nothing quite fit, but could have been many things. Narrowed it down to most likely tps or map sensors. Then I read what you wrote.... I simultaneously felt relief and like an idiot. Went outside, swapped the two plugs, started it up, and runs like a dream! I thought I was done for, as I can't afford to play the part swap game right now. You sir, are an unsung hero.

Good to hear, please use 2CarPros anytime we are here to help.

Cheers, Ken

I was driving and the car has been acting weird. The first thing I noticed is when I would push the gas pedal hard it bogs down which reminded me of when I had a crack in the rubber air intake hose. Drove some more after getting gas went about 10 miles and it lost all power and stalled luckily its a manual so I got over to the side of the road safely. My mechanic replaced the EGR valve and now it starts but the engine bogs down a little before 2000 RPMS. My mechanic said it may have jumped time but unsure. The timing belt won't need replacing for another 35,000; the cap and rotor spark plugs and wires have been replaced a month ago. Replaced Coolant hose recently. Used seafoam to clean out the carbon because it was having problems for about a month with running. It would run fine just idle kind of low and not perform properly. Any ideas or suggestions? I have looked and seen people suggest fuel pressure and dirty intake manifolds, would that cause the engine to die so suddenly? It performed great and literally overnight the engine started having issues. I have sprayed with carb cleaner all the vacuum hoses and there are no leaks. HELP PLEASE :D

Hello,

It sounds like you have a plugged fuel filter here is a guide to help you change it out with diagrams below to show you on your car.

https://www.2carpros.com/articles/how-to-change-a-fuel-filter

Check out the diagrams (Below). Please let us know what you find. We are interested to see what it is.

I changed the fuel filter all fixed.

1999 Honda Accord 5 speed experiences a sudden loss of power, gauges drop to zero for a split second and come back. the other day it died on the road then came back to life 15 minutes later. Maybe related issue, the vent switches on dash, select the two on teh right, Defrost and another (can't remember now) and it turns on AC as well. Those switches are also not backlight at night with headlights on.

Mechanic looked for a grounding problem, couldn't find one, my daughter is afraid to drive it now.

Have the ignition switch checked. Symptom indicates a possible interruption of power supply. There was a safety recall on the ignition switch for the year model.

thanks! I'll have that checked. I was going to go thru all the fuses as well to see if there was a hairline crack in any. Though if it is the ignition I doubt that would be related to the vent controls and AC, maybe more than one problem ;-)

The ignition switch can affect the vents controls and A/C as it interrupts the power supply to them causing them to go haywire.

Hello,
I have noticed a power loss when driving under wet conditions recently. I would happen randomly and then go away. This will last even after the car has been sitting for a while after driving through rain. I suspect the ignition system or the crank angle sensor which is a the bottom of the crank pulley. Perhaps water getting through the connector.
The car drives normally when dry and no check engine light.
Please advise. Thanks!

Hello,

I think you hit it on the money with the ignitions system, I would install new spark plugs, wires cap and rotor.

Here is a guide to help you get the plugs changed.

https://www.2carpros.com/articles/how-to-change-spark-plugs

Please let us know what happens.

Cheers, Ken

Hello Ken
I have previously replaced the wires and plugs not too long ago. I replaced the cap around two weeks ago. The main ignition coil sits on top of the transmission on this model. Any other suggestion? Have you seen this issue before on a car like mine?

Not quite the same problem in the rain. Does the engine get wet because it rains so much? It could be the main ignition coil shorting out.

No, just regular rain driving whithout driving through water puddles.

I just changed the intake gasket set on a 1999 Honda Accord EX, the motor is a 2.3L4 I also replaced the sparkplug wires & sparkplugs with what it called for which is NGK & gapped them at .044. I changed vavle cover gasket, oil, & also added antifreeze. When i cranked it up it ran at about 900rpm & when you press the gas slowly it idles up to about 2000rpm & then bogs down & shuts off. So i went ahead & replaced the egr valve & it still does the same thing. I took the spark plugs out & checked them & they was a smutty black color on them. This is the second set of spark plugs that look like that. I undone the exaust pipe from the manifold & dropped it down thinking the converter was clogged up because it popped up a code saying the converter was effienency & then a undenified code which was P1259 before i even worked on it & it still does the same thing. Before i dropped the exhaust down, it had no pressure coming out the exhaust & was sucking in air more than blowing it out the exhaust. it has two o2sensors on it, 1 at the exhaust manifold & 1 on the converter. I dont know what is wrong. Is it possible it jumped time, it looks like the stock timing belt on it. Please help.

Check the fuel pressure if its witin specs and then comeback with the readings-start here

I am wondering I know it sounds easy but could the air filter be plugged?

Get a engine vacuum reading @ idle let me know how maney inch if vacuum you have.

Can i pick up a fuel pressure tester @ a vacuum tester at a autoparts store or does it have to be a certain one from a tool truck?

I asked a mechanic shop in town & they said replace the coolant temp sensor & i doubled check with somebody else & they said thats right. I did that & it didnt work. Could the fuel pressure regulator be bad?

The car starts fine. When in idle its kind of rough momentarily, then smooths out. Its an automatic, when shifting gears, it bogs down and sputters, acting like it wants to die and has a few times. It had been doing that for about a month. Now, sometimes, not all the time, when I give it gas it doesnt go for a few seconds, then it goes. Feels like it may be not getting fuel. The check engine light is on. I replaced plugs but did not help much.

Retrieve the code and post it up. That may be the answer to your problems.

Also, you should do a full ignition tune-up (wires, cap and rotor) not just spark plugs.

I would recommend doing some testing . Replacing parts can waist a lot of money. Get the vacuum readings and fuel readings. If you can't rent them you might be better off paying a shop to do the testing

I got the codes and they are:

P0171
P0420

DTC P0171: FUEL SYSTEM TOO LEAN

1. Check the fuel pressure
Is fuel pressure OK?
YES - Go to step 2.
NO - Check these items:
If the pressure is too high. Check the fuel pressure regulator and the fuel return line.
If the pressure is too low. Check the fuel pump, the fuel feed line, the fuel filter, and the fuel pressure regulator.

2. Start the engine. Hold the engine at 3,000 rpm with no load (in Park or neutral) until the radiator fan comes on.

3. Check the Primary HO2S or Air Fuel Ratio (A/F) Sensor (Sensor 1) output with the scan tool. Does it stay at less than 0.3 V or more than 0.6 V?

YES - Replace the Primary HO2S or Air Fuel Ratio (A/F) Sensor (Sensor 1).
NO - Go to step 4.

4. With a vacuum pump, apply vacuum to the EVAP canister purge valve from the intake manifold side. Does it hold vacuum?
YES - Check the valve clearances and adjust if necessary. If the valve clearances are OK, replace the injectors.
NO - Replace the EVAP canister purge valve.


DTC P0420: CATALYST SYSTEM EFFICIENCY BELOW THRESHOLD

1. Reset the ECM/PCM

2. Start the engine. Hold the engine at 3,000 RPM with no load (in Park or neutral) until the radiator fan comes on.

3. Except F23A4 SULEV engine: Test-drive at 40-55 mph (64-88 km/h) for approx. 2 minutes. Then decelerate for at least 3 seconds with the throttle completely closed. Then reduce the vehicle speed to 35 mph (56 km/h), and try to hold it until the scan tool indicates FAIL or PASS as the TWC test result.

F23A4 SULEV engine: Test-drive at 50-55 mph (80-88 km/h) for approx. 2 minutes. Then decelerate for at least 4 seconds with the throttle completely closed. Then accelerate to 55 mph (88 km/h), and try to hold it until the scan tool indicates FAIL or PASS as the TWC test result.

Is the test result FAIL?

YES -Check the three way catalytic converter (TWC). If necessary, replace the TWC.

NO -Intermittent failure, system is OK at this time.

What could be casuing the power steering to lose it's power, almost like it is manual steering. Any thoughts?

this could be a pump going bad, low on fluid or the seals in the steering unit itself worn out. normally when teh steering box goes it's hard to steer wehn cold then is ok after warmup.

99' Honda Accord Lx coupe with 120,000 miles. I was moving from one city to the next and my car ran out of gas on the highway during a thunderstorm. The rear brake lamp light on the dash came on and hasn't turned off yet, although the light itself isn't on unless the brake is applied. Acceleration in my car has been slower than usual sometimes immediately sometimes after driving for a few minutes. Going up hills is extremely slow. Heard it may be a clogged fuel filter, is this likely and if so can I replace it on my own?

You may have had a filter that needed to be replaced and when you run the system dry the pump sucks everything out that it possibly can to keep the engine running. Junk, sediments, etc collect and are now pushed in to the fuel line. Adding new fuel pushes it along until it gets to the filter. Yes, replace it and it is pretty easy to do yourself. After you replace it I would bet the fuel that leaks out when tipped is not very clean.

Hello, I have a 1999 Honda Accord LX 4dr that i bought from someone that refused to have it tested and decided not to fix it. The car drives okay and it is in fair conditions however; i noticed that in the morning when i do not let the car warm up for at least 30 minutes, the RPM goes very high when the car automatically gears up to 2nd. Also, when making a left or right turn and i attempt to speed up all i get is the RPM to go up but my speed stays the same or decreases. So, my work around that is get a good speed initiate my turn (left or right) and bring the steering wheel to center before stepping into the accelerator.

What seems to be wrong with the car?
Is it something that I can check or fix myself?

Your assistant will be greatly appreciated.

Hi 2fast2furious,

Check the transmisison fluid level and top up if necessary.

When engine is cold, the Idle Air Control valve would increase the rpm till it warms up sufficiently before it settles down to idling speed. That is normal unless after warming up the rpm is more than 800rpm, then you might have a vacumn leakage somewhere or the idle speed is out of adjustment.

I have a 1999 honda accord and just recently i have been having some issues. one issue is when i am in 3rd gear and up and accelerating, the rpms will shoot up as if i down shifted. it even did it while in cruise control and as i went up a hill it suddenly shot up. the second problem which i think may be related is when i was accelerating into 3rd gear, the car started to bogg down as if starving for gas. i dont know much but i can figure things out somewhat if some one can guide me. thanks in advance!

When the rpm's shoot up does the engine lurch ahead? I am checking if the problem is guage or engine.

I dont think it really is a guage problem. It surges just as if i down shifted. today it did the bog down again.

need advise...this is my only trasportation.

Check on the EGR valve. Sometimes it sticks. Then start looking for a vacuum leak, check coolant level and if full, bleed the air from the system. The Idle Air Control valve could be taken apart and cleaned as well.

My neighbor has a 1999 Accord. It has started being very sluggish upon acceleration and seems to not want to exceed 3000 RPM. I checked the air filter and it seemed fine. The timing belt was changed approx. 60k miles ago. She had never changed the spark plugs so i went ahead and replaced them. The old ones appeared white as if there was a lean air/fuel mixture. I thumbed through a manual and it mentioned there was not a servicable fuel filter on the car. The problem has become worse in the last couple of days and the engine light is on. The engine appears to be running smoothly (not missing). Any ideas on what to test? I had the ECU scanned and it gave codes for Mass air flow and O2