REALLY weird AFR pattern.
Thread Starter
Joined: Aug 2006
Posts: 5,589
Likes: 69
From: New England
I rerouted my Vacuum lines this past week and maxed out my FPR. Everything seemed fine for 5 days.... Until this morning where I got a 16.7 spike in VTEC and leane 13.4 across the whole rpm range.
Sigh, so tired of this... I really thought I resolved this. Really don't want to drive the car now.
I guess I should send out FPR to Comptech and have them Bench flow it for me.
Sigh, so tired of this... I really thought I resolved this. Really don't want to drive the car now.
I guess I should send out FPR to Comptech and have them Bench flow it for me.
Registered User
Joined: May 2011
Posts: 279
Likes: 0
From: Marietta, Ga
Are you using a Walburo (spl?) fuel pump? If you are, I have a story that very is similar to yours:
About 5yrs ago, I had just finished my s15 sr20 powered s13 hatch. All that was left was custom intercooler pipes for my spearco front mount core. I take it to a local shop that I've done buisness with in the past. Two weeks goes by and my car is still the at the shop untouched. 3rd week I decide to go to the shop and cut and weld the intercooler pipes myself.
I get there, and no one is at the shop. I call one of the mechanics and he told me he was on his way. While Im waiting for him to arrive, I happen to notice through the rear hatch of my car, that the fuel pump has been taken out!!! Not just that, but the gasoline in the tank was just left open to go stale or for things to fall into the tank... WTF...
Mechanic gets there, I ask him wtf. He calls up main dude, main dude tells him that he was dynoing a civic with a faulty walburo that was going ape shit and figured my car had a walburo so he just took mine. Seriously, who does that? Main dude tells me he will buy me a new one, so Im like whatever, and proceded to make my own IC pipes.
A week later, I go pick up my "new" walburo from main dude in an open box. I get home, and start installing the fuel pump again. As I was taking out all the components, everything was in a bag and looked new other than the fuel pump. You know that one way washer that holds the fuel filter, that you press on to that nipple on the bottom of the fuel pump. Well that nipple was scared from a flathead prying it off. I smell the fuel pump, and it smells like fuel... WTF
I go to install it and its completley different from a 240sx walburo. I end up modifying the fuel pump holder and cutting some lines to get it to work. I crank it up and the fuel pump whine is sparatic. I would fluctuate from high to low pitch whines any where from every 5 to 20seconds. I got the number on the walburo pump box and google it. And to no supprise, one of the applications was for a civic. How shitty of a shop to do something like this to a customer....
I take it to the dyno and did three pulls. First pull seem ok. 2nd pull seemed fine untill about 6krpm when the tach needle just stopped. It stayed at 6k for about 5sec then continued to redline (ugh... wtf? low pitch fuel pimp whine?). 3rd pull it took about 10sec to accelerate from 4k to 5k.
On the road, dependent on chance. I would hit a soft limmiter under accreation when ever the fuel pump wanted to act all funny. This is not a fuel cut, this is much more dangerous as instead of cutting fuel, it would produce insuficient fuel pressure. Only fuel pressure high enough for an engine to operate, but not for one under load. This in turn produced retarded high a/f's and egt's.
A few days later after hitting that soft fuel cut two dozen times, the car started idling funny. It was trucking as if it had some huge cams in it. I checked the coolant and it was fine. I opened the valve cover while the car was idling, and it was like a hair blower (uh oh). I then started checking the compression accros the cylinders. I got to the forth one, and pulled the plug. The plug was covered in oil (super uh oh). Compression was about 20-30... The excesive a/f's and egt's fried the ring lands on the 4th clyinder...
My time and my s15 sr motorset that I payed $5200 for went right to the shitter, thanks to that shitty f@#king shop and that god damn civic. So the 8k or so I had in the entire car including the chassis, I sold to a friend for 2500 blown. Looking back, I should of just bought another new $90 walburo. So I partialy blame myself for risking my engine while knowing about the faulty pump. To this day though, Im still shocked at how bad that shop did me wrong.
Anywho.. Very long story short: Check you fuel pump to make sure it is not acting up like mine was. And be carefull as it took less than a week for me to blow my motor under those circumstances.
About 5yrs ago, I had just finished my s15 sr20 powered s13 hatch. All that was left was custom intercooler pipes for my spearco front mount core. I take it to a local shop that I've done buisness with in the past. Two weeks goes by and my car is still the at the shop untouched. 3rd week I decide to go to the shop and cut and weld the intercooler pipes myself.
I get there, and no one is at the shop. I call one of the mechanics and he told me he was on his way. While Im waiting for him to arrive, I happen to notice through the rear hatch of my car, that the fuel pump has been taken out!!! Not just that, but the gasoline in the tank was just left open to go stale or for things to fall into the tank... WTF...
Mechanic gets there, I ask him wtf. He calls up main dude, main dude tells him that he was dynoing a civic with a faulty walburo that was going ape shit and figured my car had a walburo so he just took mine. Seriously, who does that? Main dude tells me he will buy me a new one, so Im like whatever, and proceded to make my own IC pipes.
A week later, I go pick up my "new" walburo from main dude in an open box. I get home, and start installing the fuel pump again. As I was taking out all the components, everything was in a bag and looked new other than the fuel pump. You know that one way washer that holds the fuel filter, that you press on to that nipple on the bottom of the fuel pump. Well that nipple was scared from a flathead prying it off. I smell the fuel pump, and it smells like fuel... WTF
I go to install it and its completley different from a 240sx walburo. I end up modifying the fuel pump holder and cutting some lines to get it to work. I crank it up and the fuel pump whine is sparatic. I would fluctuate from high to low pitch whines any where from every 5 to 20seconds. I got the number on the walburo pump box and google it. And to no supprise, one of the applications was for a civic. How shitty of a shop to do something like this to a customer....
I take it to the dyno and did three pulls. First pull seem ok. 2nd pull seemed fine untill about 6krpm when the tach needle just stopped. It stayed at 6k for about 5sec then continued to redline (ugh... wtf? low pitch fuel pimp whine?). 3rd pull it took about 10sec to accelerate from 4k to 5k.
On the road, dependent on chance. I would hit a soft limmiter under accreation when ever the fuel pump wanted to act all funny. This is not a fuel cut, this is much more dangerous as instead of cutting fuel, it would produce insuficient fuel pressure. Only fuel pressure high enough for an engine to operate, but not for one under load. This in turn produced retarded high a/f's and egt's.
A few days later after hitting that soft fuel cut two dozen times, the car started idling funny. It was trucking as if it had some huge cams in it. I checked the coolant and it was fine. I opened the valve cover while the car was idling, and it was like a hair blower (uh oh). I then started checking the compression accros the cylinders. I got to the forth one, and pulled the plug. The plug was covered in oil (super uh oh). Compression was about 20-30... The excesive a/f's and egt's fried the ring lands on the 4th clyinder...
My time and my s15 sr motorset that I payed $5200 for went right to the shitter, thanks to that shitty f@#king shop and that god damn civic. So the 8k or so I had in the entire car including the chassis, I sold to a friend for 2500 blown. Looking back, I should of just bought another new $90 walburo. So I partialy blame myself for risking my engine while knowing about the faulty pump. To this day though, Im still shocked at how bad that shop did me wrong.
Anywho.. Very long story short: Check you fuel pump to make sure it is not acting up like mine was. And be carefull as it took less than a week for me to blow my motor under those circumstances.
Thread Starter
Joined: Aug 2006
Posts: 5,589
Likes: 69
From: New England
I was afraid of that and got my self Australian FULLBLOWN 340 instantly when I was getting AFR issues. Helped but not much. Thanks for the post tho. I now have a fully functional and fine Walbro on the shelf... HOWEVER it also made noises and changed pitch constantly when it was installed. Full Blown is silent.
Joined: Oct 2002
Posts: 8,044
Likes: 6
From: South Florida
I was afraid of that and got my self Australian FULLBLOWN 340 instantly when I was getting AFR issues. Helped but not much. Thanks for the post tho. I now have a fully functional and fine Walbro on the shelf... HOWEVER it also made noises and changed pitch constantly when it was installed. Full Blown is silent.
I feel u have an electrical issue. If the pump changes pitch then voltage os fluctuating to it. Rewire ur pump to battery and see of that works.