Miles: 40,392
Year: 1993
Model: Base
Mods: Downpipe, Silicon Hoses, AST.
Recent Work: Broken sensor in fill neck. Had to remove the fill neck to get the sensor out. I have done all work myself, so I am not exaclty a stranger to the engine, and I had everything hooked back up correctly.

Symptoms: When I was driving down the road the other day, I noticed the check engine light was one. There were no symptoms in the car itself, as perormance was fine, and boost & temps (water) were normal. The light went off a few minutes later, and I thought it was just a bad sensor or something, and thought I would keep an eye on it.

Two days later, I was driving the car down the road when the check engine light started going on and off sporadically. There was no particular pattern to the on/off (not a steady flash, but more like on for a second, off for 3, then on for a split second, then off for a second, etc. etc.). I then noticed the car have a SEVERE power loss (engine, not electronic) in accordance w/ the light coming on/off. The power would resume when the light went off.

Thoughts: My first thought is that it is a fuel mgt problem. Either an issue w/ the injectors, or perhaps a bad sensor causing the A/F ratio to go wicked rich, or wicked lean, therefore causing the power loss (and possible detonation). Good news is that I got the car off the road before something like that happened. I don't plan on driving the car until I can get some education from you fine folks.

Any thoughts from the Guru's? Help is much appreciated as it is spring time, and our cars love to be driven in the spring.

Thanks in advance.

Steve

 

You try pulling codes?

 

the check engine light doesnt stay on long enough to get a code. Like i said, its intermittent for periods of less than a second.

 

get the code first, makes sense right?


the code flickers because whatever is broke is going on and off.

 

shouldn't the codes be stored in the ecu and pop up when you pull the codes? I dont understand your response.

 

Yes, the codes are stored in the ecu. Pull the code(s) they will point you in the right direction.

 

Not always true... I had my speedo flicker out on me and it would only pull a code if the light was on. Code came up speed sensor error. replaced the gauges, never came back. The problem he is having with the power loss is 2 things. One... It's something that is serious enough that the compter is causing a fuel limit, or the engine to hold back power so that you dont blow your **** up. A factory ECU will safeguard if the light comes on for certain codes. Not sure exactly but this info is coming from David at KD Rotary. With the light on you will only get the performance you get when you first start the car. 6 lbs on one turbo... kinda like drivin a VW.

All i can say man, is have someone hook up a Modis, or snap on scanner to it, to try to catch it with the light flashing. the modis will record it if it comes on. hook it up under the hood, then have someone sit in the car with the scanner, and drive around a little. not hard. Let me know if this helped at all.

 

The stock ECU saves ALL codes it flags. If that light is coming up, it will still store a code. If the check engine light comes on, it's a problem that's directly related to the engine running.

I've never figured out why people see the check engine light, post about the problem, but don't take a minute to pull the codes and investigate that problem.

Dale

 

I was not aware the that ECU stored all codes. I'll check it on friday when I get home.

Hypothetical question: If the check engine light was on before by the previous owner, but he never got it checked out, which code is the most recent, the first, or the last?

 

The code are not stored by time but by number. If your worried about old codes, I'd note the exsisting codes, reset the ecu, take the car for a drive untill the ck. eng. light comes on (or symptoms return) then ck the codes again.

 

Any other thoughts before I go hood diving?

I've heard "reset the ECU", i've heard "get the code, even though you wont know which is which", and I've heard "reset the ECU, then try to break it again".

The 2nd seems to be the most reasonable, as I don't risk blowing up my engine trying to.... well... blow up my engine

Anyone else?

 

Honestly, over the past 2 years I had my car, I've had no reason to pull codes. It really is a simple procedure however (do a search). I dont understand how you are worried about blowing your engine if pulling codes or resetting the ecu does not require the motor to be running.

I have no idea what you mean by this statement

 

Here’s my new recommendation. Post in the regional forms and ask for a recommendation on a local rotary shop. Take it to them, they will have a diagnosis for you in know time.

 

<rant>

"This statement" was simply outlining the various suggestions I have received.

My concern about blowing my engine from resetting the ECU is as follows:

I reset the ECU so it erases all previous engine codes. Then I go out and drive the car to try to get the check engine light back on. During my driving, I blow my engine b/c the problem was actually fuel related, causing detonation (and perhaps blowing the engine).

As I said before, I will pull the code & post further on my findings. I was simply looking for some other kind soul, who perhaps has had these symptoms before, to post their experience. I don't think I was looking for a host of comments on where I should post/repost, or how you haven't had this problem.

One could argue that if you are not responding to this thread, then you have not had this problem. Is it really necessary to explicitly tell everyone what is so plainly obvious?

</rant>

Thanks for the suggestions thus far. Please keep them coming. I appreciate the help!

 

Dude... There was no malice in my last post, but when someone makes a statement like.......

It implies to me that your not interested in taking the time to learn about the cars self- diagnosis function and need to take the car to someone that knows the car. ( I have no idea how to do my taxes and have no interest to learn, so I pay someone to do them for me. )

Everyone replying to this thread is trying to help, but all I get from the symptoms you posted is your car runs poorly and the ck eng light comes on. If we had the codes we might be able to help.
Resetting the ecu will not blow the motor, but I wouldn’t go blasting around at wot until you resolve the problem.

 

Do not post again until you have read this and followed its instructions:
http://www.fd3s.net/engine_codes.html

 

Gadd - my apologies for misreading your post. Seemed like you were offering criticism without really helping me solve my problem.

As I said in my first post, I am no stranger to this car, and obviously have interest or I wouldnt be on here trying to solve my problem myself.

and once again - i'll pull the codes, & repost with my findings. I do not need help finding instructions on how to get the engine codes, as I use the search function on this site.

 

Off hand, sounds like you'll get a code 11, INTAKE AIR THERMOSENSOR. Transient CEL, car mostly runs OK but looses power under acceleration when the light is on. I don't think you mentioned it, but the car is probably running very rich.
If this is it, no big deal. IIRC the sensor is about $45 from Malloy, but you have to pull the UIM to change it out. Check the plugs afterward too. I've been procrastinating on mine.

Good luck.

 

Chill out man. That's no way to talk to someone...esp when he hasn't been hostile w/ you. It's not your place to tell ppl to post or not to post.

I know Steve personally, and he's a very hands-on lemme-try-and-fix-it-myself kinda guy. The prob here clearly isn't his lack of desire to do anything...it's his worries from rumors he's heard about clearing the ECU codes etc. A simple "why don't you ..." will get much better results. Or better yet, read Sgtblue's post. Simple, to the point, and very helpful.

The thing that pisses me off is that people like yourself often expect so much of ppl on the forum just because you make an invalid conclusion that "if you own an FD, then you better know a hella lot about cars, and be damn near an expert w/ these FDs." 1) You can't pick and choose what kind of people join the forum. If you wanna do that, get your own forum, and pre-screen the members Hell, at least Steve's not asking about F&F bodykits and madd fast shiftin yo! 2) The forum is here so that those who do NOT know can learn from those who KNOW. So you will ALWAYS have a nice wide spectrum of ppl's knowledge about cars and FDs. If you don't like one end of the spectrum, really, in all honesty, that's too bad. And it's also a pretty crappy outlook, because you're being "elistist." 3) If you wanna REALLY roll w/ the big dawgs, the guys who know the MOST aren't even on the forums, or barely every post. Look at Steve Kan or Ray Wilson's post count. So I'm kinda confused how you fit in. You know, post, but are impatient w/ those who don't know....

If I thought in the same manner you did, I'd kirk out at every single patient I see, because I'd think "Gosh you're too damn stupid to be alive...you've had your body for how many years now, and STILL don't now how to take care of these 1001 illnesses that are possible?" Cuz that's pretty much exactly what you're doing. If you wanna help, help. Cut the bull, forget the sidetalk and criticism, and help. Otherwise, really, stop trolling. It distracts us who are still learning.

Don't take this as me being hostile toward you...I just get pissed cuz you get pissed so easily as if everyone is supposed to know better than to ask this... or is already supposed to know that. Maybe you're expecting too much out of everyone?

Steve, I dunno why everyone's jumping down your throat on this. Don't pay it any mind. I know you love and care for your bone stock FD w/ 40K on it...and being over-careful is the only way you're gonna keep her in such good shape. So don't sweat it man. Check those codes as suggested, and I'm sure someone wil be kind enough to help you out w/o all the unnecessary side comments...

~Ramy

 

The reason why everyone tells you to "pull codes" is that with many problems it is very hard to tell exactly what the problem is by merely looking at the symptoms. Just because people haven't posted solutions is because the solution could be any number of things, and they don't want to blindly guess at what it may be. It could be fuel, spark, or boost related, meaning it could be anything. It does not mean that people (myself included) has not had similar problems.

Look at your post

Therefore, people tell you to pull codes because it will lead you in the right direction. This is how I fixed my ignition problem (nothing really f*cked up has happened in the past 2 years though, thank god).


Honestly sgt blue likely could be right, but is revsteve ready to start replacing components left and right in attempting to solve the problem if people start offering any number of solutions? (rhetorical question, I know he isn't and will pull codes )

I dont think we're jumping down his throat. I think the viewpoint to be taken is that if you ask a question and 5-6 ppl keep giving you the same answer, then perhaps their viewpoint is correct? (perhaps not)

It's kinda nice that FDNewbie is willing to stick up for the REAL newbies though

 

I understand you 100% and agree w/ you. I was just saying that I think Steve was afraid of resetting the ECU because of rumors he heard, that's all.

Absolutely. I didn't mean to imply that his post was the end-all and THE answer...just that his demeanor was very helpful, vs "listen dumbass read the FAQ, learn to pull codes, give us some meaningful info, THEN come back and talk to us. Oh, and OF COURSE resetting the ECU won't damage your engine....dumbass." I'm just real big in the way things are said

Again, I'm just real big in the way things are said. But I think Steve now knows what he needs to do haha

Compared to ppl like Hyperite, I'm a noob too!

 

Ramy - Thanks for the kind words. I do agree with you that people are very testy and impatient on this board. Its really the reason that I stopped posting. I get in and read up every now and then, and usually only post when something stumps me or I can help out a newbie. In any event, thanks again.

Sgt. Blue & POS7 and whoever else, thanks for the help. I have no idea how this got so out of hand.

For those of you that are still interested, I pulled a 12 & 18 (Throttle Sensor - narrow & full). I'll be adjusting the TPS this weekend and let you know if that fixes my problems.

Anyone have any advice or pitfalls on adjusting this (besides what is on FD3S.net?

 

People told him to pull the codes, he wanted a second opinion. Why speculate? Pull the codes.


If a patient called you and asked why he didn't feel well, would you ask questions to figure out the illness? or just grab at one of those 1001 possibilites? Say you ask him if he has a fever, but he doesn't want to go get a thermometer. Just move on and start guessing?

https://www.rx7club.com/3rd-generation-specific-1993-2002-16/how-can-you-tell-test-something-draining-your-battery-421324/
Just you.

 

The ecu will only set a code for the TPS if there is an open or short circuit, just being out of range will not set a code. the unit it self is very harty and rarely fails, the first thing I would do is clean the connector well, reset the ecu and see if that fixes it.

 

If the patient told me he was scared because he heard a thermometer could hurt him in some way, I wouldn't laugh at him like he's a dumbass. I'd just calmly reassure him no harm can befall him, and encourage him to use it. That's exactly what happened here. All you had to do was assure him that resetting the ECU then pulling new codes couldn't cause damage.

Ask me if I care...