Help with overcoming fuel cut!
#1
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Ok, please hang in there as this may be a long one.
My 1994 WRX (yes it's still off the road!) had a decat downpipe and centre section, ninja back box, K&N induction kit, ported headers and a Walboro 255 fuel pump. The car may also be chipped in the land of the rising sun but further investigation is needed.
Before I took it off the road (as in SORN'd) it was getting really bad fuel cut in 3rd, 4th and 5th gears. Having a look on hear, SN and talking to a few people there are certain options available to me to remedy this.
1. Get an Apexi PFC ecu and have it mapped for my car - £950
2. Buy an electronic boost controller and have it set up correctly by Extreme Scoobies (for example) - £250
3. Buy a Scoobyecu/VOS chip and have it installed along with a dawes device to control the boost. - £250
Now, option 1 would be great but it's going to take me a year at least to save the money and I can't live with the car for that long. I'm leaning towards option 3 as I've had some good feedback about the VOS chip and think it's a good bet.
However, I would like some valuable input from all of you guys and gals and point me in the right direction as I've been stewing over this for a while! Many thanks!!!!!
Ben
My 1994 WRX (yes it's still off the road!) had a decat downpipe and centre section, ninja back box, K&N induction kit, ported headers and a Walboro 255 fuel pump. The car may also be chipped in the land of the rising sun but further investigation is needed.
Before I took it off the road (as in SORN'd) it was getting really bad fuel cut in 3rd, 4th and 5th gears. Having a look on hear, SN and talking to a few people there are certain options available to me to remedy this.
1. Get an Apexi PFC ecu and have it mapped for my car - £950
2. Buy an electronic boost controller and have it set up correctly by Extreme Scoobies (for example) - £250
3. Buy a Scoobyecu/VOS chip and have it installed along with a dawes device to control the boost. - £250
Now, option 1 would be great but it's going to take me a year at least to save the money and I can't live with the car for that long. I'm leaning towards option 3 as I've had some good feedback about the VOS chip and think it's a good bet.
However, I would like some valuable input from all of you guys and gals and point me in the right direction as I've been stewing over this for a while! Many thanks!!!!!
Ben
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even cheaper option is just get the dawes device (about £30) and just turn your boost down slightly. Enabling you to enjoy the car whilst saving up for the power fc or one of the other options.
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Hi Ben,
My car is in a similar state of tune to yours, and you can almost guarantee that with the totally decatted exhaust that you will be pulling more boost that the chip is mapped for... especially in cold weather!!
If you have a boost gauge fitted (if not get one!!) then take a look when in 3rd, 4th & 5th at the boost level you are hitting when you floor it...?
It will rise very quickly when first depressed, untill it settles out at where it should be (usually 16.5psi on chipped ECU's) it can sometimes boost to 18-19psi especially in 4th and 5th and you will then get fuel cut, the fuel cut can only be raised to 18psi as the MAP sensor won't recognise any higher than that.
Obviously it all depends what chip you have in there and what it's all set to, you really need to monitor boost activity and AFR/Knock to get a better idea of what the car is doing.
My car is in a similar state of tune to yours, and you can almost guarantee that with the totally decatted exhaust that you will be pulling more boost that the chip is mapped for... especially in cold weather!!
If you have a boost gauge fitted (if not get one!!) then take a look when in 3rd, 4th & 5th at the boost level you are hitting when you floor it...?
It will rise very quickly when first depressed, untill it settles out at where it should be (usually 16.5psi on chipped ECU's) it can sometimes boost to 18-19psi especially in 4th and 5th and you will then get fuel cut, the fuel cut can only be raised to 18psi as the MAP sensor won't recognise any higher than that.
Obviously it all depends what chip you have in there and what it's all set to, you really need to monitor boost activity and AFR/Knock to get a better idea of what the car is doing.
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Fit option 1 and have it fitted and mapped by AndyF if you can, but there are others, however I only can vouch for Andy. Just a solid professional.
Your troubles will be over, except the Apexi will allow you to modify time and again! (and that IS a VERY slippy slope)
Graham.
Your troubles will be over, except the Apexi will allow you to modify time and again! (and that IS a VERY slippy slope)
Graham.
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Originally Posted by 911
Fit option 1 and have it fitted and mapped by AndyF if you can, but there are others, however I only can vouch for Andy. Just a solid professional.
Your troubles will be over, except the Apexi will allow you to modify time and again! (and that IS a VERY slippy slope)
Graham.![Big Grin](https://www.scoobynet.com/images/smilies/biggrin.gif)
Your troubles will be over, except the Apexi will allow you to modify time and again! (and that IS a VERY slippy slope)
Graham.
![Big Grin](https://www.scoobynet.com/images/smilies/biggrin.gif)
The car has been off the road for a few months whilst I've been sorting it out. To be honest, I can't keep changing bits on it and going to different stages with the engine. I had a pre-conceived idea of how I wanted the car to be and it's almost there, just the engine to sort out. I just want the car to go well and be a good useable everyday car.
I'm going to put the fuel pump back to standard and see if that helps as I haven't fitted an adjustable fpr. What confuses me is that the car is running at 0.9 bar which I thought was standard pressure for this year and model so why would the ecu be cutting the fuel?
A friend has an STI type R v4 with a de-cat exhaust (not downpipe) and my car will keep up quite happily which makes me think that it has been fettled elsewhere?
Cheers for all the replies, trying to get some information together before making a decision.
Ben
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