Strange engine hesitation

[JohnS.]

I've got this weird hesitation/bog with my car. For those that don't already know, it's a 99 ex (with stock y8) with 224k miles.

It only used to do it every now and then but it's starting to do it more often. Sometimes if I go WOT in any gear, it will bog REALLY badly and the car will start shaking and...the best I can describe the sound....is it sounds like a boxer motor. The car BARELY moves, it just starts shaking violently and hardly accelerates. Then if I let off to half throttle, it will drive normal.

It originally started a few weeks ago and it happened exactly when VTEC kicked in at WOT. All of a sudden the car lurched and it hesitated up til I shifted. Same with 2nd gear. In gears 4 and 5, it bogs no matter what at WOT. Again, if I let off to half throttle, it drives normal. But anything over half throttle and it starts bogging and shaking violently. 3rd gear is iffy.

The weird part is, the symptoms are different each time. Sometimes even when I'm at 1/3 throttle in 1st gear, it will do it. Other times, I have to pop VTEC at WOT in order for it to do it. It's very sporadic and not consistent. Regardless, when it does happen, again, the car shakes violently, barely accelerates, and the engine sounds like a boxer motor.

Any ideas? My friend said it sounds like a distributor going bad?

 

[00siboy]

MAP sensor? I just commented on this on a similar post, it sounds like something that senses load, or reacts when the engine goes under a load. I think a bad dizzy would make it run bad all the time.

 

[JohnS.]

MAP sensor? I just commented on this on a similar post, it sounds like something that senses load, or reacts when the engine goes under a load. I think a bad dizzy would make it run bad all the time.

See that's what I said to my friend. But he thinks it's a distributor. I kinda trust him because he's done a ton of work on my car and he went to school to be a tech and was a tech at Acura for a few years. But I dunno.

It all started when he soldered a new MAP sensor connector because I broke the stock one. I also took the MAP sensor itself off another y8 since the plastic on that end was broken too. Can a MAP sensor get dirty? Should I remove it and spray it with something?

 

[00siboy]

You could try MAF sensor cleaner or electrical parts cleaner, it wouldn't hurt.

 

[Puma]

When was the last time you tuned it?

 

[Hecz]

Yea, Sounds like misfiring caused by a bad distributor, inside the the distributor the Iginition control module probably went bad, Actually OR is going bad. If it completely going bad, you car will not turn on because lack of spark. One time that happen to me, had to tow it home. Another compoenet inside the dizzy the ignition coil. that is if the dizzy is the internal coil type. I can see that causing your problem and that part is replaceable. Honda will tell you the ICm is not replaceble by you, but if you are a good electrician you can do it, lol. In my case i had to buy a new distributor. Coil went out first for me, then fallowed by ICM. Im wondering right now if a bad coil will actually lower life of icm faster. .... interesting.

Could be plugs?

 

[RonJ]

Stock 99 EX? What CEL codes are thrown? If you say none, does the CEL work?

 

[civexspeedy]

I doubt it's the distributor, it would likely be more consistent and across the power band if something were wrong with it. If the coils bad, it's bad and you just wont get any ignition which then your car won't run. I had a coil go bad on me on the highway at 65mph. CEL flashed for a second and then the car shut off completely and had to pull over fast. Had to tow home and bought a new distributor..

If this started after messing with the MAP sensor wiring, I'd say start there.

 

[JohnS.]

You could try MAF sensor cleaner or electrical parts cleaner, it wouldn't hurt.

I'll pick up some electrical connector cleaner after work and give it a shot. Couldn't hurt I guess right?

When was the last time you tuned it?

I'd have to check my book but as far as ignition goes, off the top of my head:
- plugs were within the last 15k
- wires/dizzy cap/rotor are probably more like 20-30k

I've been meaning to do a tune up but it gets expensive after adding it all up . If I can sell my shotgun I'll do another tune-up lol.

Yea, Sounds like misfiring caused by a bad distributor, inside the the distributor the Iginition control module probably went bad, Actually OR is going bad. If it completely going bad, you car will not turn on because lack of spark. One time that happen to me, had to tow it home. Another compoenet inside the dizzy the ignition coil. that is if the dizzy is the internal coil type. I can see that causing your problem and that part is replaceable. Honda will tell you the ICm is not replaceble by you, but if you are a good electrician you can do it, lol. In my case i had to buy a new distributor. Coil went out first for me, then fallowed by ICM. Im wondering right now if a bad coil will actually lower life of icm faster. .... interesting.

Could be plugs?

I don't know crap about that stuff. I'd rather get my car taken in to get tested or have someone else test it. I don't have one of those voltage meters or whatever anyways.

Plugs SHOULD be good but who knows. Car does have a lot of miles....

Stock 99 EX? What CEL codes are thrown? If you say none, does the CEL work?

Stock except for an aftermarket intake and header. No codes and CEL does work. Comes on while the fuel pump primes and I just had a code a few months ago I cleared.

I doubt it's the distributor, it would likely be more consistent and across the power band if something were wrong with it. If the coils bad, it's bad and you just wont get any ignition which then your car won't run. I had a coil go bad on me on the highway at 65mph. CEL flashed for a second and then the car shut off completely and had to pull over fast. Had to tow home and bought a new distributor..

If this started after messing with the MAP sensor wiring, I'd say start there.

I'll try cleaning the MAP sensor after work. If this continues, I'll try to see if I can scrap a used distributor. I know these things are a dime a dozen too and I've seen a few sell on a local board for $20-$40.

 

[Jersey8]

Yea, Sounds like misfiring caused by a bad distributor, inside the the distributor the Iginition control module probably went bad, Actually OR is going bad. If it completely going bad, you car will not turn on because lack of spark. One time that happen to me, had to tow it home. Another compoenet inside the dizzy the ignition coil. that is if the dizzy is the internal coil type. I can see that causing your problem and that part is replaceable. Honda will tell you the ICm is not replaceble by you, but if you are a good electrician you can do it, lol. In my case i had to buy a new distributor. Coil went out first for me, then fallowed by ICM. Im wondering right now if a bad coil will actually lower life of icm faster. .... interesting.

Could be plugs?

awhile back i had an issue similiar to john's and hecz's. sporadic misfiring, stalling, bogging, etc. for like a month lol. it was so bad that it would stall and then i couldnt get it to start. eventually after multiple attempts and some hopes and dreams it would start lol. thought it was the MAP sensor too. changed it out, but still had problems.
then one day i was driving on the highway and it just finally died, would not start again. had it towed to a shop and it was indeed the distributor.
i have my money on dizzy

 

[JohnS.]

Damn.... How bad can you throw timing off if you have it turned too much a certain direction? I know you can sort of mess with timing by loosening the bolt and pivoting it forward or backward.

 

[CHILD]

you could have a fouled spark plug. sometimes it happens rather quickly. I had that happen to me.

 

[JohnS.]

you could have a fouled spark plug. sometimes it happens rather quickly. I had that happen to me.

Spark plugs are cheaper than a dizzy. I'll try spark plugs after cleaning the MAP if that doesn't work.

 

[Puma]

Spark plugs are cheaper than a dizzy. I'll try spark plugs after cleaning the MAP if that doesn't work.

I was thinking it's plugs/wires if not the dizzy. I had this similar issue on my old crx. replaced those and it helped, but turned out to be MAP and main relay as well.

 

[CHILD]

yeah, my b16a did it to me. The number 2 one was all crusted over and the others looked perfect still. I dont know what caused it either.

 

[JohnS.]

I was thinking it's plugs/wires if not the dizzy. I had this similar issue on my old crx. replaced those and it helped, but turned out to be MAP and main relay as well.

Damn. Spark plug wires are expensive too! Oh well... At my mileage, it probably wouldn't hurt to do a tune-up a little earlier. I'd have to check my books but I'm sure I'm due for one either way.

 

[Decipher]

TPS? I'm just throwing that out there since you said it depends on how much pedal you're giving it. I know the throttle position sensor is pretty easy to check for proper voltage. Might be worth looking at if you can borrow a meter. From what I understand, the voltage should be .5 volts at closed throttle and 4.5 volts at Wide Open Throttle, with a smooth transition between the two positions... no jumps.

For some reason, it doesn't sound like a distributor or plug issue to me. But I could be wrong. The ICM or coil would cause trouble under normal driving as well, rather than just under hard acceleration... I would think. But start with the cheap/easy stuff. Checking voltage is free. Replacing expensive ignition components is not.

 

[treeafodo]

My bet would be spark plugs. It's worth checking at least. It's cheaper then wires or a dizzy. Lol

 

[JohnS.]

TPS? I'm just throwing that out there since you said it depends on how much pedal you're giving it. I know the throttle position sensor is pretty easy to check for proper voltage. Might be worth looking at if you can borrow a meter. From what I understand, the voltage should be .5 volts at closed throttle and 4.5 volts at Wide Open Throttle, with a smooth transition between the two positions... no jumps.

For some reason, it doesn't sound like a distributor or plug issue to me. But I could be wrong. The ICM or coil would cause trouble under normal driving as well, rather than just under hard acceleration... I would think. But start with the cheap/easy stuff. Checking voltage is free. Replacing expensive ignition components is not.

Should I just take off the TPS and clean it along with the MAP? Or check voltage? Out of curiosity, why would voltage effect the TPS and how does it happen in the first place?

 

[Hecz]

spark plug wires are like 20 bucks. No time for that fancy jdm bs. you need regular-ass replacement parts. Do start by diagnosing plugs and wires first. I believe If it was some sensor, you would have a CEL. A bad igintion coil will not trigger a cell.