Bogs around 1500...EGR ports?

[AccordWarrior]

Hi all,

My mom's been on my case lately about something going on with her car. The car has a bog/hesitation around 1500 rpm, only after the engine is up to normal operating temperature.

If I'm driving along and it kicks into OD and the revs drop to around 1.5K it'll go fine, but when I tap the accelerator, it bogs and then accelerates. If I keep it above roughly 1.5K it runs like a champ. However, if I accelerate from a dead stop, or if the engine speed is below 1.5K, it does the same bog.

A quick scan of the service records that came with the car when we purchased it shows that the car had the EGR valve cleaned out, the fuel filter replaced and a bottle of fuel system treatment added. There was no notation of thet EGR ports being touched in the intake manifold. The note said the the mehanic suspected the ECU, but I have a hard time believing that honestly. I reset the ECU after it threw a one time CEL (O2 sensor heater), but that hasn't returned since. I've always been under the impression a stock ECU would either be good or bad, since a fuel/timing curve can't randomly change. If my car was auto, I'd swap in my ECU just for kicks, but I'm aware a manual ECU won't run an auto (that's correct, right?).

I'm ruling out the transmission as any culprit, as it happens in any/every gear, and I had the fluid changed at Honda about 2 months ago. The sport light isn't blinking, and I have no reason to suspect a malfunctioning TCU or anything of the like.

Searching on this topic, I could only find a few solutions and one of them was that it was EGR related. It makes sense in a way because it only starts to act up once the car is at normal operating temperature, and from my understanding of the EGR system, the system only turns on if you will when the engine is warm.

Could clogged ports be the root cause of this? I know this can be a tedious task, so is there any way I can test my theory without having to actually go in there and drill them out before hand that won't do any damage to the car?

I thought about just disconnecting the EGR, but will that affect the drivability enough that I won't be able to rule out the EGR as an issue?

Like I said, I did pull up similar topics, mainly posted by alb_accord, but I couldn't find a resolved answer for my question.

Thanks in advance.

[NAiL05]

You can put on a blockoff plate for the EGR and see if that works. Disconnecting the EGR will throw a CEL. Does it do it below 1500 also or just when it hits 1500?

[AccordWarrior]

You can put on a blockoff plate for the EGR and see if that works. Disconnecting the EGR will throw a CEL. Does it do it below 1500 also or just when it hits 1500?

If I kept it under 1500, it's fine as well. It's just right when it crosses that threshold it bogs.

My Mom's been whining about it lately, but will not let me do anything major as far as work, so that's why I was wonder if there was a quick and easy way to tell if it's EGR related. I might just quickly fab up a plate this weekend.

My reasoning for suspecting EGR was that it only does it when the car's warmed up, and from what I've read, the EGR opens/works at 1500 rpm, right?

[NAiL05]

It only open when your cruising if I remember. As for acceleration and decel it doesnt work. Interesting. I would say bad gas but that would bog and miss through the range a bit.

[AccordWarrior]

It only open when your cruising if I remember. As for acceleration and decel it doesnt work. Interesting. I would say bad gas but that would bog and miss through the range a bit.

Really?

It's definitely not bad gas...it's been doing it since we bought the car. What gets me is it won't do it when the car is first started and cold...so I need something that will only come into affect when the car's warm.

Come to think of it, I couldn't tell you if it does it under hard acceleration. It's only under light accelration it bogs. Actually, I'll play with it this weekend and see f I can't narrow down when it does it.

It usually doesn't bother me due to my driving style, but it's been driving my mom nuts.

[NAiL05]

Haha yea. I wold say Throttle position sensor since those wear out eventually but just test it this weekend and see whats up.

[AccordWarrior]

Haha yea. I wold say Throttle position sensor since those wear out eventually but just test it this weekend and see whats up.

Interesting...I'll have to research about that tonight and see if I can't figure out what's up with that this weekend.

[blackice]

I would say block the egr port off and install the sensor back over it temporarily to test it out. I ran this way for almost a year on my h22 with stock p13 with no cel thrown and it solved my hesitation/slight bogging problem under light acceleration. Good luck man

[wrichards2005]

First, try blocking off the EGR like you said above. Its most likely the valve, but maybe it could be blocked off ports or something...

I used to have that problem all the time, (91 automatic), I guess its more noticeable on the autos or something...

If it turns out to not be the EGR valve, try disconnecting the connector at the oxygen sensor. It could be running in open loop mode until the car heats up, and after it heats up, it could be changing your fuel map and causing it to bog. If you disconnect the sensor I'm pretty sure it will cause your car to stay in open loop, even after its warmed up, and that will give you an idea of whether or not its O2 sensor related.

My last 2 suggestions sound VERY strange, but both made a big difference when I was running into issues with bogging:

Check your coolant level. My car used to bog all the time when I first got it, I checked the coolant, it was low (and dirty), so I changed it out, and it ran a LOT better.

Also, check or replace your thermostat. I ran into a problem earlier this year where everything mechanically seemed normal, but I was bogging. I decided to change out my thermostat (mainly just because I had never done it in the 2 years that I owned the car). I took the thermostat out only to find out that it was partially stuck, and wouldn't open/close fully. I had no indication because the car wasn't overheating, nor was it overcooling. But it did make a big difference.

Good luck man, its an annoying ass problem... hopefully you get it straightened out.

[Granite CB7]

My CB did the exact same thing under light acceleration, not WOT acceleration, regarding the EGR, there's a diff. You'll really notice it around 1800 rpm when the EGR valve is open. I believe above and below 1800, the valve is closed. I really think you have clogged ports. Stuff a quick DIY plate between the IM and valve and do afew light runs w/ it and I'm confident it will be like night and day.

[mrhonda]

EGR isn't open under acceleration, only at light throttle at cruising speed. So even if the ports are clogged, this would have no affect on acceleration.

However a bad EGR solenoid could cause this, if the solenoid is applying vacuum to the valve too early. I have seen that before.

[Accord R33]

check the base timing..

[Granite CB7]

EGR isn't open under acceleration, only at light throttle at cruising speed. So even if the ports are clogged, this would have no affect on acceleration.

However a bad EGR solenoid could cause this, if the solenoid is applying vacuum to the valve too early. I have seen that before.

I believe you but I swear before I blocked my EGR, under very light, gradual acceleration, my engine would shake/bog around 1500-1800 but above it was just fine. Once I blocked the EGR, no bogging @ all w/ ever so slight acceleration. Thought I'd share

[phatdoughnut]

Autos run really rich for some reason, my wifes has black sut(sp?) on her bumper(white car.)

SEcondly, check out the plugs etc, just a suggestion, easy check atleast, same thing with the air filter. Maybe shes bogging cause of a dirty filter.

[TheNextAZN]

mainly an auto problem? anyone have a similar problem like this for manual? Because i do.. lol. I bog at around 2k. that is with light accelleration, and in all gears at warmed up/normal operating tempuratures. it hasn't bothered me much cus i give it a little gas and brings it back up to normal. guess i can try to block my egr port.. see if that fixes it. how are things working with ur car now AccordWarrior?