First, sorry for the long post, but I thought I'd give the 3-day history of my issue.

Here's my deal, Saturday, I went on a little road trip the other day (240 miles, I did say little). After a few hours, my gf and I jumped back in my Z and the car took longer to start. This NEVER has happened before! Normally, my car starts quick and true. In fact, it caught me SO off guard that it didn't start as I didn't leave the key in the start position.

Anyhow, after about 15 miles I noticed the SES light on. I don't know how long it was on, that's just how long it took me to notice it.

After our movie was over, I started the car again. And yes, it took longer to start again. This time I was prepared and let the key in the start position longer. The car drove fine on the way home.

I used the technosquare ECU code technique and discovered that my engine code was a P0171. I cleared the code and started the engine back up. It still took a little longer to start and I thought all was well.

Sunday, I drove my car and the damn SES came back on. I took the car to Autozone and they read the code (again, P0171) and cleared it again for me. The guy there said I might need an O2 sensor to fix the car, but to drive it and see what happens.

The car drove the same as the last time I cleared her. Once again, the SES came back on. After doing searches for posts that specifically discussed P0171, I only located this post and another, which talked about an loose/leak in the intake after the MAF.

That being said, I did notice that my intake wasn't snug after the MAF. The orientation of my Popcharger caused my OEM intake tube to angle (bunch up, if you will), causing the tube to angle rather than sit flush when clamped down to the MAF housing. I was excited about this because when I first installed the Popcharger, it was flush, so I thought that perhaps I found a 'leak' and the true root cause.

Since my Popcharger was DIRTY, I changed my intakes. I installed a 2006 OEM intake with a KN filer (I've run with this and never had an issue). Then, once again, I cleared my SES and crossed my fingers! Something I want to point out, KN did not have excessive oil on it. In fact, it was pretty darn close to the condition it would be after receiving it from the KN people.

Unfortunately.......that was not the solution!

Now here's what is confusing me:
My car has not tripped a SES light since I installed my other intake and got a good seal on the intake tube and MAF housing (almost 48hrs), however, my car is still taking a little longer to start and I have noticed my MPG has been decreasing. I'm down from an avg. MPG of 23 to 18 now!

I'm guessing it's my O2 sensor like the Autozone person said, but why isn't my SES coming on!? Wouldn't the strange readings trip it!? It did before?

In addition, as of Monday night, my car is now unable to handle WOT. In fact when I throttle down, she stumbles/hesitates. So, that would again lead me to believe a bad O2 sensor. I'd guess after 50% throttle, she starts to stumble. After a point (maybe 75% throttle), the car doesn't react any different, meaning, I could floor it and it doesn't accelerate.

So.....I'm hoping that someone can push me in the right direction.

Thanks!
Larry

 

Anyone? Bueller? Bueller? :P

 

Here is what they state is wrong with my car,
"FOUND BAD FUEL PRESSURE CAUSED BY BAD FUEL PUMP, PUMP ONLY PUTTING OUT 23PSI AT IDLE, 19 WHILE ACCELORATING. NEEDS FUEL PUMP $454.29 FOR OEM"

I'm assuming that these readings are low for our fuel pumps. Is that correct?

Also, this morning, my car tripped another SES. I haven't checked the code (running late to work), but I'm betting same code.

The strange thing is......my car didn't stumble under WOT or hesitate. In fact, it ran decent (still felt OFF).

I'm confused....

Can someone help me out? I feel like I'm talking to myself. lol

 

Does anyone concur or reject the dealer's opinion that my issue is a fuel pump?

Car's MPG is still crappy (like 14mpg avg.). And it does have issues with WOT (I checked for curiousity sake).

Thanks!

 

It's funny, I'm the only one responding to this thread and it's my own.

Anyhow, here's what happened-
The fuel pump was bad, however, it was not the only issue causing the SES. If you recall, I mentioned that I searched and found the SES code I received could be caused by an intake leak and that I noticed that my POP Charger was not sitting flush (I thought there might be some air escaping, even though it didn't look like there would be a leak......you never know!). Ergo, I charged my POP Charger out for an OE air box, but that did not solve my SES issue.

The dealer noticed that one of my plenum bolts was loose! In fact, three of them needed to be torqued down correctly. I was pretty shocked, as I torqued them down per OE spec. when I installed my spacer.

That being said, if you have a plenum spacer, I'd check your plenum bolts if you're ever under the hood. You never know!

Hope this helps someone in the future! I know I could have used this thread (or some replies from others....lol)

 

THis is a pretty entertaining thread. you started and finished it all by yourself. lol

glad you found your problem.

 

Hey man, at least you solved the problem. GL.

 

How can nobody reply in this 15 days.....

 

I'm just glad that I was able to find my car's issue. There have been PLENTY of occassions where this forum and its members have saved me head aches and money spent at the dealership!

Thanks!