Ive had my Rx8 since 2004 (Its an 04). I just recently, in July 07, got a new engine.

Anyways, for the last two weeks when I come to a stop my car has what I can only describe as hiccups. The rev needle as most of you know is at 1 when the car is on and you are at a stop. When these hiccups happen the needle goes from 1 to .5 or even less if the hiccup is really bad. When these hiccups happen the car shudders, which is scary for me because whenever the car shuddered like that it meant that the car was on the verge of dying or the car just shut down by itself (if it was a really bad shudder) It really feels for me that the car is like dying but it somehow manages to stay alive. Then earlier I checked from the outside of the car to see if I can hear it from the outside when the car hiccups i noticed the rear lights, as well as any other lights, dim and nearly die out when the car hiccups. it cant be the battery because I got a new battery in July 07 before I got my new engine


So anyways Ive searched on here and have not found anything similar to what I am going through. If anyone can share any light on whats going on Id appriciate it.

Oh and btw if this turns out to be a major problem I have no choice but to get rid of the car. Even though I love it. Im actually looking online to see the value of a 2004 GT with a new engine and 58xxx miles. 3xxx being on the new engine

 

I have the same thing going on and I'm taking my 8 to the dealer on Monday or Wed. I'll post up my info. Read into tech threads on here. Someone is on engine #3.

 

could it be a problem with one of the ground wires?

 

Its hard to say. You just have to use up all your options before you find the prob

 

Please tell me whats up with your 8 when you find out DOMINION. Since we seem to have the same problem. Maybe it's the exact same problem(ground wires)

i looked through the tech threads(only 2 pages worth? WTF happened?) and saw nothing similar to what im experiencing.

In other news, Im looking at a 2004 WRX. White. something like 28xxx miles.

 

Idle problems are commonly due to the Mass Air Flow (MAF) sensor being dirty. I read about the exact problem you described just yesterday. The owner pulled the MAF and sprayed it with carb cleaner (there's a DIY on this board). That fixed it like new. I'm not saying this is definitely your problem, but it's something to look into. Also, check your air filter.

 

Exactly what I was thinking as well and here is why...

About 6 months ago I put the K&N Typhoon Gen 2 Intake on my car. I had to take the MAF off and obv. reattach it with the new intake and I cleaned it at the same time and it did that rough idle for about a week b/c it had to get used to the high flow of air coming in the intake. I think as well, if it is dirty and all of a sudden is cleaned, it kind of needs to get used to it. When I put my stock intake back on and dropped in the K&N filter, it did it again, but only for a day or two and now runs smooth again. The MAF needs cleaned once in a while and then needs to be run to get a uniform reading of air through the sensor.

This may not be your problem if it is a HUGE shudder or not, but I def. experienced the tach dropping from about 900 rpm to 500 rpm (shudders) and then it kicks back up. It did go away...

 

you might need plugs!!! Also, reset your ecu... this helped me.

 

Was it fine right after your engine swap ?

It could be bad rebuilds

 

This is a completely new problem tha started happening about 2 months after the new engine

 

just went through the exact same problem..

checked maf. ok.

changed plugs. needed to be done anyway.. found a plug that was loose.. and oil on the outside of the plug..

replaced plugs, much better. still idling a bit low, but the ecu has not had enough time to adjust..

btw, this is my second engine.

beers

 

Quick aside-
Swoope, when did you get your second engine? How many miles are on it and have you ever experienced the marbles in a can (with either engine)?

Back on topic: I reset my ECU (both RAM types) after I dropped in my K&N panel filter and I noticed the idle would drop from 800 to 500 every 20 seconds or so at idle. This lasted a week then cleared up. I think the ECU got all the readings it needed and is now back on track. However, mine never came close to stalling...

 

first engine was replaced at 56k miles.. ran great.. with premix. not so good without..

this one has 22k miles on it.. i just had a drop in mileage, and idle and stalling issue..

i think the plugs, (and the fact that one is now tight...) have solved the issue..

will keep you posted here..

i have coils to change next it that does not do it..

i need to give it several days to see where we stand..

beers

 

If I take the battery out. My engine will stall the **** outa me on the first couple hours of driving.Embarass the **** outa me at the stop lights

After that, it idles fine and stuff.

guess the ECU programming is kinda messy, probably have something to do with my intake, or both.

Whatever. My engine is running fine after ECU learn its lessons.

 

Spark plugs, coils, bad gas, or vacuum system issue can all be part of the issue. I had a similar issue and Mazda replaced my coils based on multiple misfires that were stored in the computer.

 

The dimming lights are just an effect of the alternator slowing down enough to not keep up with demand. Side-effect, not really the problem.

 

Good luck!

 

Yeah I'm very interested to hear about your experience. Was the new engine covered under warranty and did the dealer give you any grief about all the mods?

OP- Good luck, let us know how things work out for you.

 

I checked my MAF cleaned it and found that the blue pipe(I have the RB intake) came loose when I touched it. I hadnt even started to unscrew the clamps. It turns out it wasnt properly connected.... Which is odd because I havent taken it out since I cleaned it before the swap. And when I put it back together I KNOW i put it back and made sure the connections were tight.

Could they have taken it apart when they rebuilt the engine? Not the actual intake but the tubing that leads to it.

In any case I tried putting the pipe back in place and it wouldnt line up... And not only that but the rubber tubing that holds it in place on the intake side has ripped in half due to the strain of it not being in place and coming in at an angle. The tubing on the engine side is like an inch higher than it was before the swap. So there is no way for the tubes to match up properly.

This weekend im going to go back to stock and see how things work out.

Even after I cleaned the MAF I was having a rough idle.

 

Good decision. Put the stock box back in and see if it helps. If the RB box is misaligned you're going to have issues.

 

that would do exactly what you are having an issue with.. and just put it back together right.. nothing has changed between the new and old engine. everything is in the same place..

beers

 

engine covered by warranty, yes.

grief about mods, no.


beers

 

Don't forget to vheck the neutral switch and the plug under the TB. Make sure you don't have a vaccum leak.