bauermd

iTrader: (1)

The only thing that has been mentioned to me at different points in trouble shooting is low fuel pressure/volume. The dealership sent diag info to their engineers and thats what they said. When my pump was replaced last week the tech noted that the volume of fuel when he disconnected the line was not good.

Now if this was a low pressure/volume issue, why am I not throwing lean bank codes? also why does it not happen right away if the ambient temp is lower. This is so confusing just trying to think about.

bauermd

iTrader: (1)

Put my stock cats and J-pipe on today. Returning the CAI and TB spacer back to stock also tomorrow. Found a '14 5.0 Premium with NAV 6speed for 23k. Cant beat it...

screaminz28

iTrader: (1)

Sorry for all the troubles you've had. I'd say drop another 5 G's or so and get a 2015 - that thing looks great!

bauermd

iTrader: (1)

Went and looked at the '15 5.0 6SP. They wanted 33,500 before anything and 36700 after everything was said and done. Just a tad out of my range. Was a great looking car though.

screaminz28

iTrader: (1)

Ouch - yeah for another 13K, I'd go for the 2014 as well. Not many cars as fast as the GT that you can score for that little money.

Bogie

Just a couple thoughts/ideas:

-Have you tried disconnecting your MAF sensor and running without it for a while?

-Not on a Honda/Acura, but I've seen this same intermittent issue almost exactly on point and it turned out to be the cam position sensor which was intermittently failing/providing false readings.

Good luck!

bauermd

iTrader: (1)

I tried to disconnect the MAP and the car idled REALLY high and stalled when hitting the gas. I have since took the PCD and JPIPE off the car and the car is running completely fine now. The ECU did not like the flow of them for some reason...

EddieOnAZ

What so everythings good now? Your problems are gone?

screaminz28

iTrader: (1)

That is really odd. I wonder if you were getting some weird reversion in the exhaust that was screwing with the primary o2s.

bauermd

iTrader: (1)

Yes, problem is completely gone and the car drives fine now. Still has me wondering though for sure...

corrado85

iTrader: (1)

glad to hear!

are you keeping your car?

S2K_MoZo

I had similar issues in my S2000 where it would backfire, sounds like it's a boxer engine and hesitate some days and some days it won't. It was my knock sensor. Knock sensors get really hot and since they are plastic, if anyone touched your knock sensor, it's probably trashed. It will not throw a code if it's like that and my S2000 or Civic Si didn't throw codes either. If the problem comes back, put it on a dyno and the car running super rich/not making any power will tell you it's the knock sensor.

Again, this is a guessing game since there are too many things involved but an old knock sensor touched by someone can break it and you will only find out if you put the car on dyno or just change it.

bauermd

iTrader: (1)

Car hasnt acted up at all since changing the exhaust. It hasnt hesitated once from a stop either. I might do a little more investigating on the Knock sensor though.. all those symptoms I had also.

I do plan on keeping the car, unless someone comes along with the right amount of money. I have replaced so many thing trying to find out whats wrong, the car runs like a dream now.

S2K_MoZo

Yeah, I ended up doing the same with the S2000, changed everything from ECU to plugs to God knows what else. I was on a contract in FL and the shop was lazy. The first guy "checked" the knock sensor and it was fine, a month later they finally put it on dyno that I had been saying for a while and then they said it's knock sensor...the second guy who touched the sensor said it was so lose that he took it out by hand. Not sure if they knew what they were doing but that was the only "reputable" shop according to people in FL. Glad I'm not there anymore lol.

I hope it runs fine man, it's a beautiful car and nothing sucks worse than your car being sick. Maybe if your kids are sick and they keep you up all night but at least you can go drive and feel fine after that lol

Glad to hear all is well. Keep us posted

Aman

Glad to hear car is running well!

bauermd

iTrader: (1)

So I stated above that the problem appeared to have corrected itself. Well last night and this morning it is back. I am not sure if I just did not hear it and feel it as much with the stock exhaust on, but it is for sure still there. When I had the PCD and J-Pipe I could hear it just because the exhaust was so loud.

I will be looking into changing the knock sensor this Friday. It is no where near as bad as it was with the exhaust though.

BukvaMan

Dont waste your money, i tried that long time ago with zero change.

You could have changed the modulator already ...

bauermd

iTrader: (1)

I completely electrically isolated the entire VSA system with no change to the symptom.

"1601.88" is the price from a discounted parts site for the VSA module. You really think that is more logical then replacing a 33$ Knock sensor when multiple people have already suggested it?

I really appreciate the attempt to help, but I do not have any reasonable belief that this is VSA related

corrado85

iTrader: (1)

pick one up from junk yard!

bauermd

iTrader: (1)

ok so 300-350$ from a junk yard < 33$ Knock sensor

bauermd

iTrader: (1)

No offense because I really appreciate the help from you and everyone else on this forum. You are telling me to replace the VSA module because it fixed your problem. I quoted a few messages where you also said the O2 Sensors fixed your problem, to your VSA module, to your TB, and back to your VSA module. This is why I am not going to just go out and try and find a salvaged VSA or a new one for that kind of money.

S2K_MoZo

Do not buy a knock sensor from a junkyard. Knock sensors are bolted on to one of the hottest parts of the car and since they are mostly plastic, they melt and can't be messed with. Biggest reason why knock sensors go bad without CEL is when people touch them while doing something else and once you touch a knock sensor which was exposed to heat, it will disintegrate and won't work.

I know they are expensive but before buying a new one, put your car on dyno and see what your AFR looks like and what the graph looks like. Just my .02 cents.

bauermd

iTrader: (1)

When I mentioned the junk yard, I was talking about other members mentioning taking a used VSA module. I already ordered the replacement knock sensor. It is cheaper then reserving dyno time. Although I would love to have it on a dyno..

S2K_MoZo

I understand but there are a lot of shops who would rather do 3 or 4 pulls for $40-$50 than just let their dyno sit. Call around and see who has a dyno and how much would they charge for just 3 pulls. Just tell them that all you need to see is data on the screen to see if your AFR is off and knock sensor is bad. They may charge you half hour labor at the most. There are some nice people out there willing to help, you just have to call and find out.

Are there any performance shops around you who will let you do just a couple of runs for cheap?

I know here in Dallas, there are tons of shops and hookups since there are huge car communities and FB groups. Try to ask people on s2ki, ford or other sites/fb pages and someone may point you in the right direction. Although, I truly hope this knock sensor got knocked lose when you messed with exhaust stuff and new one should fix everything. Hoping it will all work out man. Good luck!

bauermd

iTrader: (1)

Replaced knock sensor and wire this morning and all seems normal. Only time will tell. The old sensor fell apart when I was taking it off, the connecter just completely fell off . Hopefully this was the issue, if not, it was only 32$ total to replace wire and sensor.

S2K_MoZo

That's very common and that is why I said to buy a new one since they fall apart real easy. Hopefully that was it and it will fix all your issues. Working on car, you have to be careful to never touch that sensor or else you end up replacing it. If it goes bad, you get CEL but if you touched it and messed it up, it won't give CEL but car will drive like crap since it won't detect knocks properly and your AFR would be off.

Good luck man, keep us posted.

bauermd

iTrader: (1)

So the problem has not been noticeable for the last few weeks until yesterday. I stated the problem is REALLY bad if I go driving for a while and then shut the car off for 5-10 minutes and get back and start driving. It happened yesterday. I drove home (17 miles), and had the car off for around 3 hours(which was enough for the car to completely cool down which when this happens, problem wont happen) and then drove to the bank (7 miles). I was only at the bank for 10 minutes and the car was off, got back into it and immediately the car was jerking and hesitating with throttle. I got onto the road and gave it a decent amount of gas and it felt like there was 0 fuel getting to the motor. It was surging pretty bad throughout the RPMs.

I thought I had fixed the problem with the new knock sensor but I guess not.

The only things not replaced are Coils/Injectors/Head gaskets and then trans and engine internal components.

Any other advice guys?

S2K_MoZo

Sorry to hear man that the problem is back. Coils won't go all bad at the same time and you'll be able to trade the problem by swapping coils. Injectors are the same way, they can't all go bad at once unless it's your ECM/ECU or wiring harness, even then there should be some kind of CEL I would think.

Head gaskets would have other indications too. Is your coolant overflow clean? Any dirt or anything in there? Can you call around for a dyno shop and see if they can do a few runs just for diagnostics purposes?

bauermd

iTrader: (1)

My coolant is by no means CLEAN. like not completely transparent as it should be. It is dark but that my be normal just from looking down at it, the sides of it are blue just from light entering the container. I will take a picture today for you. I am not losing coolant or anything though.

bauermd

iTrader: (1)

Ok everyone, car ran decent the past month or two because the weather was really cold. The temps have raised to above 60/65 this past week and the problem has came back. The only modification to the car at this time is a Injen CAI. I have had 2 different sources say my fuel pressure is weak when the problem is happening but have no been able to actually verify this or find a fix for it.

The car will run perfect as long as I do not drive it more then 15/20 minutes. I was driving around yesterday and wondered out of town and the car started to drive like sh*t again and fell on its face out of no where. It honestly feels like I am running on 3 cylinders. The noise the engine makes is real baffled and it sounds like its just missing a whole lot. I can put the pedal almost to the floor and it doesnt get any better until the car decides to downshift but then it just happens in the lower gear also. Happens in both manual mode and automatic mode.

Now being 2 different sources said my fuel pressure was weak, I have tried to just replace things related. I have a brand new OEM fuel pump assembly in there which replaced the pump, filter and regulator I think. I have not replaced the injectors but I did swap a few of them just pretty much taking shots in the dark. All the top and bottom O rings of the injectors are brand new. I feel like something is heating up and just malfunctioning but I cant think of anything else anymore. The dealership swore up and down it was because I had removed my cats. I went through the trouble of removing the test-pipes and J-pipe and TB spacer just so they wouldnt have that to blame anymore. Now they wont take the car in anymore without me paying 125$ fee just to get it in the door for an hour or "troubleshooting". Last time the Service manager told me I might just have a problem that will never get solved.

This is my last resort post, I do NOT want to get rid of the car due to how much money i've dumped into it in the last year or so but I may be at the end of my efforts.

Any last suggestions?? ):

screaminz28

iTrader: (1)

Is your car under warranty? If so, why not just go to a different dealer? I'd think it would have to be if they say they are going to charge you to bring it in. You'd have to do that no matter what if it was not warrantied. Youve since returned the car to stock and the issue still occurs so I don't see how they can charge you. I think it's definitely electrical - but finding it could be near impossible without lots of troubleshooting.

I think they may have to have a datalogger on it and drive it continuously - the problem will be visible on a datalogger/diag tool when it is happening and that will help lead to the root cause.

As for the low fuel pressure diagnosis - was that an 'observed' issue when it is happening or people just saying "sounds like low fuel pressure"?

bauermd

iTrader: (1)

The issue was data logged multiple times by the dealership and they sent the log files off to the engineers in CA they said. The engineers came back and said its either a bad tank of gas or I have low fuel pressure. Clearly not the bad tank of gas...

I had an independent mechanic look at it all the way down in FL when I took it there and they said when they were hooking up the pressure gauge, the fuel was extremely low pressure but said that was just by the looks of it.

The car is not under warranty that I know of. It expired at 70k miles and I just rolled over 100k yesterday.

When the problem is not happening, it drives like a dream. I have replaced so much stuff that almost everything minus the actual motor and trans that is runs great. There is no transition period to it running bad, its just like hitting a switch. No CELs either.

bauermd

iTrader: (1)

Car has been back at the dealership for the last 6 days (for free, no charge this time to take it in). They just called and said they are seeing "weird parameters" from the MAP sensor and fuel pressure sensor. Not enough to throw a cel they said. They instantly are pointing their fingers at my CAI now. If you have read any part of this thread, they initially blamed it on my exhaust which has since been removed and sold. The MAP is brand new also.. they told me my throttle body is aftermarket and its an OEM one.. argued for 5 minutes about that and just told him ill bring the "OEM" one back that I took off. I replaced it with a new OEM one for troubleshooting efforts. So now were at me replacing the CAI and "aftermarket" TB and going from there.

sauceja

iTrader: (2)

Just read this thread. Damn man I have no words for what you have been going through.


A couple suggestions. The gas cap code being stored is an easy fix if you didn't fix it already. It is an 80 dollar valve near your throttle body.




As far as your issue. It sounds heat related definitely. I would suggest maybe running a different ATF fluid such as amsoil. Read a few guys discussing similar problem of the transmission actually getting heat soaked.


That might explain why the removal of exhaust helped also. If you were getting extra heat from exhaust directly onto your transmission super heating it.


You may also want to run an aftermarket transmission cooler to help.


It seems you don't have an issue on cooler days, and when the car isn't heated up.
You also have the issue only in stop and go traffic and not when you are at constant hwy speeds where you have better air flow.


This is what I would take a look at personally. It sucks to see you spent so much money throwing parts at a problem.


If the transmission starts having problems, codes or not, it will affect the TCU which in turn will affect the ECU.
The back firing is most likely the ECU adding fuel to become a rich condition which will aid in cooling the engine.
You can have lean back fires and rich back fires. Both are bad.


And shame on those Acura techs for saying they can't datalog.
They either don't know what they are looking at or didn't send the data to Honda HQ for analysis.


And they have the tools to hook up an external gauge to monitor fuel pressure. They sound like retards.


I feel for you deeply. Your car looks very clean. I hope you resolve the issue. I am subscribing to see the end of this.

sauceja

iTrader: (2)

When I worked at Honda, the s2000 was notorious for knock sensor issues.

bauermd

iTrader: (1)

Appreciate the lengthy response. The Gas Cap code was fixed a little while ago, so was the knock sensor. The dealership called and told me its my cold air intake now. They initially blamed it on my exhaust and when I brought it back with stock exhaust they suddenly changed their minds.

The transmission fluid has been completely changed 2 times since owning the car and most recently at around 85k miles with the timing kit and oil pump replacement. When they finally data logged the car, the "engineers" came back and said I was losing fuel pressure or I had a bad tank of gas. Ruled out gas right away and started chasing the lost fuel pressure. This is all going off Acura saying its a loss in fuel pressure. I have not even thought about the transmission problem but it for sure makes sense. Only thing is sometimes the problem just completely goes away out of no where. It is so intermittent its kind of annoying.

Literally the only things I have not replaced are:
COPs
Injectors
Actual motor/trans
Fuel lines them self

I can't think of anything else that hasnt been replaced that is related. I actually just picked up a stock intake just to entertain the dealership at this point. Just so they stop pointing fingers are mods done to the car. After the CAI is stock, nothing else is modded on the car window tint and suspension. Which they might tell me car is too low and not enough airflow.

bauermd

iTrader: (1)

Alright, the car has been at the dealership going on over 2 weeks now. I went and test-drove with the master tech last night and he had a live-data laptop hooked up the entire time. We came to the conclusion that the laptop is saying the car is running completely fine. He can definitely tell there is a problem with the way the car is running though. He recognizes that. We went back and kind of had a pow-wow with a few of the other techs and came to the conclusion that no one knows what is wrong with it and 99% chance I will never get it fixed.

I did verify they checked compression and checked valve clearance and those were both ok. He also did some live-data on the transmission and did not see anything wrong there either. Solenoids were fine.

I think I might just have to give up....

screaminz28

iTrader: (1)

This dealership sounds like it has no experienced driveability mechanics. They are grasping at straws and blaming everything they can think of just because they have no clue.

I think this is heat related. Honestly it could be something as simple as connector that is only halfway plugged in and comes loose with heat. Believe me, I've seen it before.

You need to find a new dealer that has REAL techs, and not parts swappers.

sauceja

iTrader: (2)

Tell them to take off a fuel line and put some gas in a container and let it settle and see if the fuel has slime in it.


I have also seen this on a civic. Had transmission codes and some other CEL's.


Found it by accident when the HDS tool said it was low fuel pressure.
The gas tank had a tremendous amount of slime in it. I had to remove the fuel tank and completely empty it and hand clean the inside.


After cleaned and re-installed. Ran some good fuel through it at a high rpm and it pushed all the crap through the injectors. Replace fuel filter and never saw the car come back to the shop after that.

sauceja

iTrader: (2)

As far as the tech's telling you after market parts are your problem. They are idiots. But I am sure their service managers are putting up a fight about not being factory parts.


That sounds more like them not wanting to admit they have no idea how to fix it. And right about now would be a good time to get corporate involved.
I am surprised they haven't asked for an engineer or a master tech from another facility to come and diagnose.