Jeremy_Hi

Hello there,

I've been using the threads from the New Member Forum, https://www.rx8club.com/series-i-tec...t-here-222280/ and https://www.rx8club.com/new-member-f...causes-249529/ to try and diagnose a misfire I had a few days ago, and I'd like additional opinions from owners more experienced with the RX8 than I.

Here is the information I can provide about my car, which could relate to the issue:
-2004 Manual: 185,000+kms (115,000+mi) owned since Nov 2014 & 176,000kms
-Compression test back in Oct 2015 came back within healthy range
-average fuel mileage has been around 19/14 mpg (highway/city), Note: I often do not attempt to save fuel
-Cat Converter seems to be in good health (not clogged/glowing) but cannot confirm
-old coils (unsure of age), but were recently (February) inspected by the dealer's rotary technician and reported OK. plugs and wires replaced summer 2015
-fuel pump: as far as I know, is as old as the car
-ESS and Throttle body both need to be cleaned, MAF cleaned Late 2015
-found some oil in the intake (overfilled oil, or vacuum leak?)
-I have not had the opportunity to pull a misfire code, but I would consider it a random misfire

Now, the Story:

So, I recently had the opportunity to drive to high speed, in a controlled manner, of course. At full throttle, in 5th gear, at approx 8500rpm, I suddenly experienced loss of power. I could feel it through the gas pedal, I looked at the dashboard and saw the flashing CEL. I took my foot off the gas, and took the vehicle out of gear, and the engine shut off/stalled. I stopped the vehicle and was able to start it again and after some cautious driving, the vehicle seemed to be performing as usual for me.

Based on what happened, I suspect this could be a sign of a failing fuel pump, but I am still learning about how vehicles and the RX8 run, so any additional incite would be greatly appreciated in helping me solve this problem. I realize the problem could be caused by any or a combination of common/uncommon problems. I do love the RX8 and I'd like to maintain it to the best of my ability.

I will be glad to provide any additional information you might find relevant to the issue. Thanks in advance,

Jeremy H

wannawankel

Nice speed: At full throttle, in 5th gear, at approx 8500rpm,

RX8Soldier

iTrader: (24)

You know that list of things you typed out, which could be related to the issue and need to verify?

Verify those.

EDIT: It even spells out how to go about verifying these methods in that misfire thread you posted. Don't just guess and hope for the best.

Jeremy_Hi

It's clear to me that I should be verifying which of the possible issues it could be related to, ie. measuring the pressure in the fuel lines, (which I do not know how to do, though I'm sure a quick search could help me with) and I am aiming to work on such things. (inspect/clean ESS, etc)

The purpose of this thread is to ask if there is any additional insight/advice someone could give me based on the problem I had. Perhaps someone has seen something like this before and can share what they had found.

As I'm still a novice and am also a new member, not everything is clear to me when reading through the forums, and of course, I have no problem going about searching and reading other forum posts to learn what I can, but I wanted to post here before I got deep into the process on my own.

Thanks,

Jeremy H

RX8Soldier

iTrader: (24)

Totally understand, and I give you credit for searching.

But we can only offer advice based on what we know. The thread you posted is a compilation of many years of verifying these exact issues, all rolled into one.

So what you should do is go through the process of elimination using that thread. There are even links in that thread detailing the "DIY". Should you follow the steps and still have issues, THEN report them here. Otherwise, we're just feeding you the same info that's already in that thread.

gsmith51234

Sounds exactly like my problem when my fuel pump was starting to fail.

9krpmrx8

iTrader: (46)

-Compression test back in Oct 2015 came back within healthy range
A test from over a year ago is meaningless now

-Cat Converter seems to be in good health (not clogged/glowing) but cannot confirm

Test it, assumptions don't help you. Buy a laser thermometer and get on youtube

-old coils (unsure of age), but were recently (February) inspected by the dealer's rotary technician and reported OK. plugs and wires replaced summer 2015

The dealers don't have a "rotary technician" and most dealer techs are useless so I highly doubt he properly tested each coil

-fuel pump: as far as I know, is as old as the car

Age doesn't matter, verify that you have fuel pressure that is within spec

-ESS and Throttle body both need to be cleaned, MAF cleaned Late 2015

Don't clean the throttle body unless you are running an aftermarket intake that doesn't filter well, the throttle body is probably not dirty. Clean the ESS, it can cause misfires if something is amiss. Clean your MAF again, you had oil in your intake.

-found some oil in the intake (overfilled oil, or vacuum leak?)

More than likely it is caused by excessive crank case pressure which is typical on a tired engine. Tick tock, tick tock.

-I have not had the opportunity to pull a misfire code, but I would consider it a random misfire

The flashing of the light indicates a misfire but it still helps to have the actual code. There are a few things that can lead to a misfire, you need to troubleshoot, not guess. Get the code and follow the FSM procedures for that particular code.

http://foxed.ca/rx7manual/2003mazdar..._S01_0016.html

Jeremy_Hi

Thanks RX8Soldier, I understand where you're coming from. Good advice.

And thank you for the informative response 9K, I appreciate it. I didn't mean to make assumptions about the coils, compression, cat, etc., I was just listing all of the information I had available to me, as to eliminate confusion/additional questions. I certainly understand it may not all be relevant or conclusive.

I'll get to work and perhaps update this thread after I've worked through all the troubleshooting.

Thanks,

Jeremy H

iTs Ghastly

On an added note, when cleaning MAF, i suggest using MAF cleaner. This might sound obvious, but some people have attempted using more harsh products such as carb cleaner, and though it may or may not damage your sensor, it is best to use what is designed for your MAF, not just what you have on hand. ESS is easy enough to clean, a 10mm socket with an extension is all you need if i remember correctly. make sure it is free of any metal shavings, and properly cleaned. Oil in the intake , as 9k said, isn't necessarily a good omen, but it is worth noting that you're far from the first to experience this, and an installation of an oil catch can may benefit you. Coils were likely not tested appropriately, it would be a wise investment whether you need them or not to go with the BHR coils, and change the plugs while you're at it, provided you have the money to do so. A garage should be able to test your fuel pressure, or you can do it yourself, i myself got a digital fuel pressure gauge when i was having issues just because i knew in the future i would need a fuel pressure gauge mounted in the car. As williard stated, comp test a year ago means next to nothing, and you need to properly check the cat. If you do not need emission testing, and you can, i would just gut your cat, though this will likely cause a CEL, unless you have an accessport. Gutted cat is generally reguarded as safer as there is nothing that can clog, and cause a potential engine faliure.
You get the point by now though, test the things you know can cause your issue, then report back. Otherwise we really cant tell you anything.

Jeremy_Hi

Thanks ghastly for the additional input. I did use MAF cleaner for the MAF, I made sure to do a good forum search before I messed with the MAF sensor. Hoping to clean the ESS this weekend, the MAF again, and get the fuel line pressure measured. I'll look into the BHR coils, I've heard great things about them. Hopefully they aren't too expensive. (you'd be appalled by the RX8 part prices in Canada, especially through the dealer. I'll probably have to order from the US) And I'll do some research on the emissions regulations around here, would be nice to not have to worry about the cat

BigCajun

iTrader: (1)

The BHR kit isn't technically RX8 parts.
He's a vendor here that makes the kits for RX8s, so I think it's the same price in U.S. dollars. (?)

9krpmrx8

iTrader: (46)

If you plan on owning the car for along time, get the BHR kit. If this car is a just a flash in the pan, then just get aftermarket OEM style coils.