adenarc

To start with I have a 2003 ap1 with about 61k miles, and about 23k on the motor, as far as i can tell the shop that did the swap was not very good, or the customer was in a pinch, as they swapped almost all the hardware and sensors from the old motor into the new one. Had the water pump fail within 2 weeks of having the car.

I got it about 6 months ago, up until about 3 months ago the car was working perfectly fine. I started to notice that i was redlining at around 86-8700, which i didn’t think much of as i’ve heard of people having similar issues. But over the course of about a week vtec got weaker and weaker, it dropped from redling just below 9k to less than 7k. It wasn’t much longer after that vtec stopped engaging almost entirely, if i put my foot to the floor the car would either rev all the way out without vtec, or occasionally engage vtec and redline at around 6700rpm. For clarification, when i say redline, im saying that the car was “bouncing off limiter” but instead of right at 9k where it should be, its doing it at less than 7k.
It could be misfiring but i honestly don’t know, I will try to take a video when i get the chance. On top of that it is definitely misfiring on downshifts sometimes. I bought a brand new vtec solenoid almost immediately and it only solved the issue of vtec not engaging every time, the car engages vtec with WOT every time now but still redlines just below 7k. With that i also bought brand new ngl spark plugs, a denso fuel pump, a pair of oem cam position sensors, and a brand new one battery from my local dealership. I cleaned my IACV and did valve lash pretty recently too during all of this and noticed that i have 3 different brands of ignition coils, 2 denso, one delphi and one that was completely unmarked, no serial numbers or anything.

I have a set of oem ignition coils on the way but it’s honestly a hail mary, if that doesn’t solve the issue then the car is going to have to sit at my brothers for the next few months until i can work on it again, as im contracted to go to japan for most of fall and winter.

Any info helps!

B serious

Is the check engine light on, and what is the code?

Is the car's coolant coming up to operating temp? Maybe you have a bad thermostat that is causing the car to never warm up.

You tossed a bunch of aftermarket parts (coils and fuel pump, etc) at the car, which may cause a lot of their own issues. Hopefully the VTEC solenoid was genuine Honda?

adenarc

Yes, i always let the car warm up to 3 bars, and ill usually wait another minute or two more.

I had types earlier my bad, but yeah that could be a issue, the spark plugs were ngk platinums if i remember correct, and the vtec solenoid was oem, along with the cam position sensors i put on earlier today. Thankfully i actually just got my thermostat yesterday in the mail so that’s getting put in at my brother house this weekend,

also i think the previous owner may have disconnected the cel, it does not turn on when i turn the key in the ignition before starting the car

adenarc

My bad, i also forgot to mention that the car is intermittently overheating when idling at a light or something after a extended period of driving. It happens about once a day, usually when i’m on the way home from work, ill pull up to the light at the end of the exit off my highway and its kinda a 50/50 if it jumps to 4, usually it takes a minute or two of just sitting there idling, if it does jump up i just pull into the right turn lane and start driving down the road to take a u turn and by that point it’s already back down to 3 bars, it goes back down to 3 almost immediately after i get the car moving again

B serious

I'd hook up an OBD scanner and retreive the codes. If its misfiring, there is going to be a CEL stored.

Have you checked for a broken or clogged catalyst?

And have you done a leakdown or compression test?

adenarc

That’s definitely a good place to start i’ll do that this weekend too, and if you’re referring to the catalyst for my exhaust, i don’t think i have one, im pretty sure the magnaflow on my S is as old as the car though

also no leak down test yet, will probably do that this weekend depending on if the codereader gives me a cvs receipt of codes

windhund116

Is there any chance that the VTEC solenoid filter screen is plugged?

SheDrivesIt

Where do you live? Maybe someone local can help getting you on and keep you on track as it seems that based upon the decisions you've made so far,
like you are not particularly familiar with this car.

adenarc

Im currently in virginia beach, and yeah Im not familiar with honda's at all, this is also the first honda i’ve ever owned

Chuck S

Mods: can we combine the two nearly identical threads?

-- Chuck