Low vacuum - Odd engine noise

[Flapjack]

I'm pulling out my hair here, trying to figure out my misfiring issues. I also have low vacuum at idle, but I'm not sure if that is due to the turbo cams RGR spec'd out for me. I'm sitting at -10 at idle.

Basically, the car seems to be running like butt since installing the boost controller. I installed a AEM TruBoost, very meticulously. I used spring clamps at every spot... planning ahead for +20psi.

So the symptoms I'm seeing are low (?) vacuum, and misfiring at +5000rpm. The plugs (Brisk) look like crap to me. The car is running at a 10:1 AFR at WOT (basically pegged out). Lito has revised the tune a few times, but there was no change. It was always a bit rich, but is now pegging out since the EBC install. I'm 99% sure I installed the EBC correctly. I had 7-8psi from the wastegate springs alone. Set to a 45% duty cycle, I'm seeing about 11.5psi before the car starts misfiring. Could the plugs alone be causing the rich mix?

I know this post is rambling, and I apologize. I'm frustrated and am faulting my troubleshooting skills at this time. I've gone over every vacuum line and even sprayed MAF cleaner around to listen for a jump in RPM.

On top of all this, I have some odd noise at idle. It sounds like it's coming from under the car, on the passenger side. It's very noticeable around the front passenger tire well. Here's a video:

 

[POS VETT]

These sound like symptoms on one of my cars. The culprit was a faulty (stuck open) solenoid (I can't recall the name) that regulates the vapor pressure in the fuel tank and it's connected to the intake manifold. Basically it allows unmetered air to be ingested and the car ran lean. The leak, as I understand it, would create a low vacuum condition.

Do you hear air rushing noise through the fuel filler when the cap is off ?

 

[Flapjack]

These sound like symptoms on one of my cars. The culprit was a faulty (stuck open) solenoid (I can't recall the name) that regulates the vapor pressure in the fuel tank and it's connected to the intake manifold. Basically it allows unmetered air to be ingested and the car ran lean. The leak, as I understand it, would create a low vacuum condition.

Do you hear air rushing noise through the fuel filler when the cap is off ?

I haven't noticed, but I can check. I did post a few weeks back that it was incredibly hard to fill up the tank. I've always had issues filling it, but never this bad. I wonder if they could be related.

Could it be tested by pinching the line from the solenoid tightly?

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[S197_smokn]

Puttin my money on them plugs

 

[JeremyH]

These sound like symptoms on one of my cars. The culprit was a faulty (stuck open) solenoid (I can't recall the name) that regulates the vapor pressure in the fuel tank and it's connected to the intake manifold. Basically it allows unmetered air to be ingested and the car ran lean. The leak, as I understand it, would create a low vacuum condition.

Do you hear air rushing noise through the fuel filler when the cap is off ?

I haven't noticed, but I can check. I did post a few weeks back that it was incredibly hard to fill up the tank. I've always had issues filling it, but never this bad. I wonder if they could be related.

Could it be tested by pinching the line from the solenoid tightly?

Sent from my Galaxy Nexus using Tapatalk 2

Sounds like your on to something here.

 

[ILW84U]

On the issue of low vacuum, when I had my BBR stage 2 cams I would see 8 to 10 at idle. My guess is your cams are the cause of the low vacuum and the low vacuum has nothing to do with way the car is running.

 

[Flapjack]

On the issue of low vacuum, when I had my BBR stage 2 cams I would see 8 to 10 at idle. My guess is your cams are the cause of the low vacuum and the low vacuum has nothing to do with way the car is running.

Yeah, I did a shit-ton of googling last night and found plenty of people who had -12 with cams. Another -2 is not that much of a stretch...

I got new plugs, but I won't have time to install them until later today. Has anyone listened to the video and found that engine noise to be odd? Or do built engines just sound that way?

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[recordbreaker5]

how are you measuring vac? just off of your boost gauge? have you put a test gauge on the line in engine bay and see what it reads there? I see 12-13in on my boost gauge in the car but when i measure it off the line by the motor i see about 15in

 

[Flapjack]

how are you measuring vac? just off of your boost gauge? have you put a test gauge on the line in engine bay and see what it reads there? I see 12-13in on my boost gauge in the car but when i measure it off the line by the motor i see about 15in

Yes, just measuring it off the gauge. I'm not sure if I have a diagnostic test gauge, but I'll look for one this weekend.

I guess I can understand lower vac with N/A cams, and maybe even turbo cams, as a little extra overlap isn't a big deal.

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[recordbreaker5]

Yes, just measuring it off the gauge. I'm not sure if I have a diagnostic test gauge, but I'll look for one this weekend.

I guess I can understand lower vac with N/A cams, and maybe even turbo cams, as a little extra overlap isn't a big deal.

Sent from my Galaxy Nexus using Tapatalk 2

if you send me your cam card or post the specs on here, i can compare it to my cams and see.

 

[Flapjack]

Changing the plugs made a huge difference. The car runs better all around, but more importantly, no more misfire at WOT. I attached some pics of the Brisk plugs. Before anyone mentions the two wet plugs, that's from the oil that was in the COP recess. I tried to clean it out as best as I could, but the oil sitting down in the hole got on those two plugs when I pulled them out.

I'm still having some issues, though, primarily with a P0102 code. It's very intermittent, but throws the wrench light when it happens. It seems to go away if I wiggle the MAF sensor, so I'm guessing it's either the plug, or the sensor itself. I'm going to take it apart tomorrow and check the pins. Hopefully that's all it is. It only seems to happen when I've been under the hood...

 

[S197_smokn]

Changing the plugs made a huge difference. The car runs better all around, but more importantly, no more misfire at WOT. I attached some pics of the Brisk plugs. Before anyone mentions the two wet plugs, that's from the oil that was in the COP recess. I tried to clean it out as best as I could, but the oil sitting down in the hole got on those two plugs when I pulled them out.

I'm still having some issues, though, primarily with a P0102 code. It's very intermittent, but throws the wrench light when it happens. It seems to go away if I wiggle the MAF sensor, so I'm guessing it's either the plug, or the sensor itself. I'm going to take it apart tomorrow and check the pins. Hopefully that's all it is. It only seems to happen when I've been under the hood...

[/QUOTE
Glad you got them plugs changed, what kind of MAF do yo have?

 

[Flapjack]

glad you got them plugs changed, what kind of maf do yo have?

hpx (ba-5000)

 

[Flapjack]

Hahaha, I feel like a complete dumbass. I'm not sure how this happened, but I figured out what the intermittent P0102 problem was. It must've been barely touching the pin hole, causing the random wrench lights...

 

[recordbreaker5]

Hahaha, I feel like a complete dumbass. I'm not sure how this happened, but I figured out what the intermittent P0102 problem was. It must've been barely touching the pin hole, causing the random wrench lights...

yea, that'll do it lol

 

[Flapjack]

yea, that'll do it lol

The craziest part is that that I haven't touched it in many months. I've been more or less driving it, with the occasional wrench/limp mode. Unbelievable...

 

[dysan]

Poor bugger went limp...better bring up the boobies thread and show it a few pictures...that'll straighten it right up.

 

[Flapjack]

Poor bugger went limp...better bring up the boobies thread and show it a few pictures...that'll straighten it right up.

Yeah, that's the last thing I need... my car subscribing to threads!

BTW, the car feels fantastic now. Other than me worrying about blowing the damn intake tube off, WOT is fun again. I can't wait to take the car to the track...

 

[one eyed willy]

I believe that would have been your ground signal on the MAF! Good find!

 

[lito]

I will charge you double, lol.

I was sure something was not right hardware wise.

Now get me logs to finish it up.