Hello everyone. Running out of ideas and have been to several mechanics within the past month so I figure I'd hop online and do some research as well as hit the forums as I'm completely clueless at this point and I'm trying to slim down the problem.

So here goes from the top.. I have a 1998 Accord EX 3.0 V6 that has been having RPM issues lately. Roughly 300xxx miles on her, but she has ran like a champ despite. (Only have had it roughly 6 months with no issues up until recently).

It started with the trans slipping, as expected with wear and tear and 300k miles, had that rebuilt 2 weeks ago. For the entire week after it was running great for the vehicle being so worn in general. But for the past week I have been having an issue where the RPM will struggle to go past 1500-2000.

I start the car up cold this happens, I start it up hot this happens. Sometimes I make it from A to B with no problem. But sometimes it happens 5, 10, 15 minutes into driving. I will get to around 20mph and try to accelerate and my RPM will stay roughly around 1500.. if I take my foot off the gas and then try to accelerate again, the RPM will jump a bit around 2000, but not much more. Sometimes the car will almost stall out and stutter around, but has never actually shut off. The lights dim inside and out as well during this and if I stop and idle while this is happening for a few minutes it almost sounds like it changes gears and all of a sudden the RPM will go from slightly below 1000 to slightly above and back down below and when I start driving again the car will drive normal as if there is no issue at all.

I find this normally happens around the 20-30mph mark and VERY rarely when I'm above 40mph. I have bought it to several mechanics and have been told several solutions, but they aren't entirely to sure what's causing it.. tune up, fuel pump, timing belt, canister and valve, solenoids, fuel filter, throttle body, plugged cat.. but no one has quite been able to figure it out. IT DID HOWEVER originally have a code for a missing or broken fuel cap at one point which was replaced, considering its only 10 bucks, and the problem was not solved, so I had a mechanic look at it and he told me he cleaned the fuel vent because a lot of times they get clogged and after driving it for a day had no problem whatsoever and the MIL turned off. That was a few days ago and since then no warning lights have come back on, but the problem has resurfaced and is getting worse and happening more each day.

I have also noticed lately there is a smell when this all happens that smells somewhat like exhaust and possibly burnt rubber? but I'm not entirely to familiar with the smell to begin with. Also notice a bit more coming from the exhaust and its a bit thicker, but after letting it sit idle for 10 minutes it thinned out and wasn't so bad, HOWEVER, inside both exhaust tips it was really wet and under both very very small puddles. I'm not a mechanic or great with cars by any means, but I can most likely answer any questions and any and all help would be much appreciated thanks all

 

First, do not replace any of those parts you listed until you diagnose the problem.

When the rpm struggles to get past 1500, put the transmission in neutral and see if the engine revs past 1500.

Do you have a code reader/scanner for your car?

 

I've had it read and the gas cap code was the only one that was on there, but it has disappeared since then. I do not have a code scanner though.
And while in neutral there is no problem revving.

 

If the engine can get past 1500 when the problem is happening by putting the car in neutral, I have to think the transmission is still the issue.

 

The problem has been hit or miss and it has not done it in neutral when I tested it, but since its been happening it has been progressively getting way more consistent gradually, from only doing it once a day to now it does it as soon as I start accelerating and hit the 10-20mph mark. Since it got worse today and I have to leave it in my driveway it has started to happen in neutral since I tested it a few more times in the driveway. What would I look at now ? Unless its still a transmission problem.