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Old 11-11-2009, 08:31 PM   #1
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Default Car slows down when i hit boost??

I have a 93 Greddy turboed. It's a stock kit with front mount intercooler, and bipes ACU. Lately when i go into boost the car slows down? I installed a fuel pressure gauge and it's pegged at 40 and when i hit like 5psi of boost sometimes the fuel pressure shoots up to like 60psi then back down? Is this a fuel pump or FMU problem??
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Old 11-11-2009, 08:35 PM   #2
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What FMU are you using? I don't think 90psi is very high. With the fuel pressure gauge you should pinch the return line and see upwards of 100psi. What injectors are you using? Post this kind of information in your signature please, along with your location in your profile.
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Old 11-11-2009, 08:35 PM   #3
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Do you have a wideband? I'll bet anything it's your spark plugs and wires, when was last time you changed them?
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Old 11-11-2009, 08:36 PM   #4
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wideband? afr's?
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Old 11-11-2009, 09:12 PM   #5
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Quote:
Originally Posted by Hypertek99 View Post
I installed a fuel pressure gauge and it's pegged at 40 and when i hit like 5psi of boost sometimes the fuel pressure shoots up to like 60psi then back down? Is this a fuel pump or FMU problem??
Is your fuel pressure regulator a rising rate adjustable one? If so, I think you're adding WAY too much fuel.
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Old 11-11-2009, 09:18 PM   #6
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You're probably knocking/detonating and your timing is being cut. Does it feel any quicker partial throttle? If so, then you're probably knocking..
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Old 11-11-2009, 09:27 PM   #7
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I have stock injectors and fuel pump. The bipes ACU is not pulling any timing. and i don't have a wideband.
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Old 11-11-2009, 09:27 PM   #8
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Oh i'm using the stock vortech fmu from the greddy kit
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Old 11-11-2009, 09:41 PM   #9
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get a wideband..

why dont you have one already..
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Old 11-11-2009, 09:46 PM   #10
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Quote:
Originally Posted by Tw34k View Post
get a wideband..

why dont you have one already..
Seriously, why dont you have one already?!?! Could be that youre running extremely rich making the engine to slug

Quote:
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You're probably knocking/detonating and your timing is being cut. Does it feel any quicker partial throttle? If so, then you're probably knocking..
Also could be a possibility.

Would you like to make your life easier?? Get a WB ASAP, dump your band-aids and an MS, knowing what goes on in your engine will save you lots of cash.

EDIT: I dont think you know, but most of the components of the greddy kit, except form the turbo/dp/mani, are **** and will eventually have to be replaced
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Old 11-11-2009, 09:50 PM   #11
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Well i've had this kit on my car for about 8 years now. It was a install and forget thing. So never thought about a wideband. You guys have a recommendation on which to get?
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Old 11-11-2009, 09:57 PM   #12
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most people go with the aem uego for a cheap permanent install but there are many great products out there ill let others chime in on there opinions

i own 3 wb's 2 for tuning and i have a aem that stays in the car so i can keep an eye on things.

My other 2 are the innovate lc-1 and lm-1, great for tuning but not as user friendly for beginners as the aem or plx might be
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Old 11-11-2009, 10:00 PM   #13
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Most of the members have the LC-1. I personally have the PLX 300M (discontinued). IRCC look up Tyson87's threads, he got one for $187 from ebay.

Also I strongly recommend you upgrade your engine management, if youve had the same FPR for eight years you could be in the verge of replacing it. Im actually surprised your still have the original components after all those years, I often read how bad the Greddy components are.

EDIT: AEM is also really popular
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Old 11-11-2009, 10:38 PM   #14
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Keep in mind the Greddy kit was meant to be used out of the box without a wideband. A lot of us on this here site ran it as such for quite some time. I'm not saying that it wouldn't be a good idea to get one, but the Vortech unit should run the car pig rich as to avoid any blown engine lawsuits towards Greddy. That being said, the OP should know not to touch anything until a wideband is obtained. a DIY intercooler kit from ebay would be a great and fairly cheap (although some time will be involved fitting it) upgrade. And I THINK as long as the pressure isn't touched, it'll only make the car safer, and again, no wide band would be needed. This is all assuming that the installation of the Bipes wasn't followed by a pressure jump or any other such crazy non-sensible addition of boost. My suggestion would be to buy my BEGI AFPR for $60 (see: classifieds) and at the same time get a wide band and some slightly larger injectors (1.8s) run 9-10psi safely and be happy. Everyone will say "MS MS MS MS MS", and it's true, even I switched, but it's still money, and you'll need a wide band with MS for sure, so ignoring that cost it's a $60 fpr or a $500 MS (assuming you don't build it yourself).
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Old 11-11-2009, 10:49 PM   #15
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In my opinion, Even tho some kits are designed to be bolt on and installed without any tuning a wideband is one of the most important things to have when modding a engine for power.

They are relatively inexpensive and if you know what the proper readings that your engine should be than you can easily diagnose issues you may be having ( especially fuel related ones )
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Old 11-11-2009, 10:53 PM   #16
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I bought this toy...
Innovate DB Blue Gauge, LC-1 Sensor, and Controller BEGi

Its an entire kit and it comes with everything you need to install it and run it. If you dont have an empty o2 sensor bung on your downpipe right in front of the cat, you will need to get one. The link to the kit i posted above will include everything you need including an o2 sensor bung for you to weld on there if you dont have a free one.

o2 sensor bung.. you can see it to the left side of the flex pipe..
DSCF0047.jpg

Thats what the gauge looks like
DSC01711.jpg
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Old 11-11-2009, 10:56 PM   #17
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Yes indeedy, get a wideband ASAP. I just don't like the people that say "get wideband or world will end". If your car has been running fine (although it's not anymore) for 6+ months without a wideband, chances are it won't blow up in the month or two it takes you to get a wideband. Which is the most time you should wait before buying and installing a wideband btw. wideband.

aem wideband:
http://www.autoanything.com/gauges/6...?kc=ffcategory
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Old 11-11-2009, 11:07 PM   #18
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Quote:
Originally Posted by curly View Post
I just don't like the people that say "get wideband or world will end". If your car has been running fine (although it's not anymore) for 6+ months without a wideband, chances are it won't blow up in the month or two it takes you to get a wideband.
How do you know his injectors are not acting up and hes going at 18a/f?

The fact that it was running fine but not running fine now kinda shows something is wrong.
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Old 11-11-2009, 11:13 PM   #19
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ok ok ok, bad time to bring up the wide-band-not-needed-once-proper-tune-(out of box)-is-established argument, but it had some basis.

When I got my wideband, it did indeed show I was going into the 17's during boost. It wasn't the injector's fault, it wasn't the FPR's fault, it wasn't the vortech's fault, and it wasn't the fuel pump's fault. It was the 1" piece of hose connecting the fuel pump to the pick up, which had a small hole in it, robbing pressure. My point is a wideband helps with tuning a car that's running decently, a narrow band would have told me the same thing my wideband told me, that something was wrong and I was running very lean.
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Old 11-11-2009, 11:15 PM   #20
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I dont trust Anything a narrowband says.
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