Radical A/F Readings

[supraguy31]

Well, Ive gotten pretty much all the bugs worked out in the 7MGTE of mine. this should be the last one so here goes.

If Im sitting Idle Im watching my A/F readings with my Wideband and Its jumping from 14.4 to 18.0 back to 14.1 then to --- then back up again. My RMP gauge is bouncing between 800 and 1200 rpms and its having a tendency to Sputter when it gets down the the 800 rpm levels and wanting to cut off. If Im driving down the road, It will drop the the 17.8 or so A/F ratios and bog down a little.

That would cause this. It was doing this before I pulled the VPC setup off the car. I changed everything back to Stock configuration ie.... FPR, Injectors I still have the MKIV Fuel Pump in so Im thinking that it might be the Problem. No Idea of what to start looking for. Any Suggestions would help greatly,

Robert

 

[supra8795]

Have you tried reseting the ecu to see what happens?

 

[supraguy31]

Have you tried reseting the ecu to see what happens?

Not yet. I just finally got it back on the road this morning after a Horrible weekend with it. It runs pretty good while Im driving down the road, Its just the Starting off and or Idling problem that is Irritating me. It stumbles sometimes and the A/F drops to 18.0 or --- and Sputters, Give it gas and it jumps back up to the correct reading after about 20 Seconds or so.

Robert

 

[bluepearl]

Have you tried reseting the ecu to see what happens?

Robert, try this. Sometimes the ECU can take a while to re-learn the proper settings. I sorta just went thru this when i made my ECU silly stupid. After about 50 miles, I am now at 2.5 on my VF and about 14.4 on my ratio during normal cruise. my idle is a smooth 750.

 

[starscream5000]

Pull the EFI fuse and report back.

 

[supraguy31]

I pulled the EFI fuse, Put in back in after about 2 minutes or so, Started the car up and It went crazy rich. 10.0 as a matter of fact, took it a while to finally start reading something but it finally started working. Im still getting the same really low Idle and my Wideband a/f reading are pretty lean. I will drive it tomorrow for a little cuise and see what it does after that. the onlt thing that I havent bothered with is the MKIV Fuel pump that has been in the car for a while.

 

[SPD TRP]

Check the NB02 sensor, I had a broken wire, went crazy rich--like 10.x at very low throttle and 12.x at idle

 

[supraguy31]

Sometimes when Im driving, it will be at 12.9 to 13.6, Stop for a while, get back into the car and start to drive and it will be at 15.0 to 16.0

Its the 3 wire Sensor from Autozone from a Ford Mustang.

Robert

 

[starscream5000]

Just out of curiosity, where do you have your wideband installed at and at what angle?

 

[supraguy31]

Its installed right below the NB O2 and it a little off to the Side. Is there any Specific way that they are suppose to be Posistioned to read correctly? I had this Downpipe Built so Im not for sure about how its suppose to me mounted.

Its about 2 Inches away from my NB but its off to the left side of the Downpipe if your looking from the front of it. The WB is just there so I can see the A/F Ratios, Im using the NB also which is connected to the Engine wiring harness. Im not getting any codes or anything if just Idles like pure Shit. Actually, it bounces from 13.7 all the way to 17.0 or ---- at Idle. If Driving, it will usually stay between 14.8 to 16 but sometimes it will hand up in the rich area at like 12.9 to 13.4 or so.

Robert

 

[supra87t/t4]

If your engine is misfiring your wideband will report a lean AFR due to the extra oxygen in the exhaust.

 

[supraguy31]

Well, I went out today, Pulled the #6 Plug and I noticed that I have a Small Hole in the #6 Plug wire at the coil Pack. As soon as I pulled it, It started Arching it ass off against the Small bolt that secures the coil packs down. Wondering if this would have anything to do with the Radical A/F readings.

Also, I just noticed that I have a Hole where my NB O2 bung was welded on. Basically the Weld broke and some for the Exhaust is coming out of there.

What do you all think, Could this be the Problem?

Robert

 

[starscream5000]

Get both of those issues fixed and report back .

 

[supraguy31]

I will, Its funny how you find all those things wrong when you really get down and look. Dam welders here arent worth a Shit.