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Lagging problems in low rpms and rattling noise at high rpms

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Old 12-17-2013 | 04:51 PM
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Lagging problems in low rpms and rattling noise at high rpms

Ok, I've searched and searched and can't find symptoms quite like mine.

Symptoms:
- takes a few seconds to turn over but has good battery

- I can't really notice a lag in 1st gear but in 3rd and 4th it's really bad. Anywhere up to 4,200 rpms if I step on the gas it just lags and won't accelerate untill it hits about 4,500 rpms and it feels like it hits a powerband.

- also occasionally in high rpms I can hear a rattling noise and when pulling up hills it's worse and I lose power noticeably.

I had an engine light on for a day and it went back out before I could read it.

All my mods are:
M2 performance straight pipe and catback exhaust, CAI and replaced plugs wire and ignition couls about 5k miles ago and that's about it

Here are two videos

This one is the lagging with the pedal to the floor
http://youtu.be/fYgA51u4HW8

This one is the lagging and rattling noise pulling up hills
http://youtu.be/IQ-wU56346k
Old 12-17-2013 | 05:03 PM
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The 8 doesn't put out a lot of power under 4k rpm. Flooring it at low rpm won't produce much more than half throttle or so plus if your spark is weak all the extra gas isn't going to burn well.

As for the rattle, could be just about anything. Is it from the engine? Undercarriage? Rear end?

Edit: plugs etc were replaced. How about your last compression test?

Last edited by RotoryVirgin; 12-17-2013 at 05:07 PM.
Old 12-17-2013 | 05:28 PM
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No this isn't something normal I've had my 8 for 2 years now and it's never been like this I step on it and it won't accelerate it would accelerate ten times fast than usually and it kind of sputters
Old 12-17-2013 | 05:30 PM
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Would it be possible my plugs are fowled because my engine flooded about 2 months ago and it took forever for it to turn over I actually had to get my starter rebuilt
Old 12-17-2013 | 05:51 PM
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Some more information such as mileage and year would be helpful.

The rattle is rather upsetting. I think it's time to schedule a compression test.
Otherwise, clean your air filter if you haven't done so already and verify all the intake valves (SSV, APV, etc.) open and close smoothly.

Last edited by tpb7463; 12-17-2013 at 05:54 PM.
Old 12-17-2013 | 05:55 PM
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Yeah that's what I'm thinking it's time for a rebuild or replacement. Its a 2004 with 113,000 miles
Old 12-17-2013 | 06:23 PM
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Coils
Old 12-17-2013 | 07:09 PM
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I just replaced the coils though in the summer
Old 12-17-2013 | 07:16 PM
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Yikes, well you need to take your baby to the doctor lol for a proper diagnosis, becuase thats the same problem I had before I had my coils replaced.
Old 12-17-2013 | 07:21 PM
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Yeah lol that's what I'm thinking I'm thinking it's about time for a rebuild
Old 12-17-2013 | 07:25 PM
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Ohhhh just looked at your profile you have a 2004! That was my first rx8 that year had major problems, it was the codes! They couldn't get the codes right in the computer. Basically your gonna have to do the recalls if they are still open for your engine. If I can recall the computer wasn't in sync with rengine, too much gas or not enough gas. Call corporate at 1800-222-5500 ask about the recalls for your 2004.
Old 12-17-2013 | 07:34 PM
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I'll give that a try thank you!
Old 12-17-2013 | 07:37 PM
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Um. Huge amounts of misinformation here. Not even sure where to start.

1st:
ignore anything coderedalert posted. Sorry coderedalert, but you have a lot to learn.

2nd:
This isn't a dead engine from the video. Dead engines that are THIS far down on power will be unable to start short of a pull/push start, and definitely not when hot. You can keep a almost zero compression rotary alive and reving fine as long as you don't let the revs fall too low.

3rd:
Your plugs and/or wires are shot if you didn't replace them at the same time as the coils. If you didn't, you may have killed your new coils from fouled plugs and/or failing wires (increases resistance against the coil discharge and overheats them fast). Even if you did replace them, you almost certainly have a clogged cat from either the failing coils or the flood. It's one of the only things that will produce a severe but smooth power loss like that. Basically the engine is being robbed of lots of power as it's trying to push air through. The rattling could be anything from SSV valve flutter to chunks of cat rattling to seals chattering on the housing under the strain of trying to accelerate with a huge clog preventing easy expulsion of exhaust gases. If your cat is clogged, continuing to drive it will lead to engine damage, O2 sensor damage, and eventually a car fire. (no, I'm not exaggerating). Pull your cat and take a look in the header side. If you can get away with a brief drive without a cat installed (it will be incredibly loud and there will be extensive fumes under the car), then you can test to see if removing the cat did indeed clear everything up.

4th:
If it isn't your cat, you need to get an OBD2 reader, a bluetooth adapter one works well paired with your smartphone and an OBD2 app, and do the mode 6 test to get misfire counts and any pending codes. Clean your MAF, your ESS, reset the ESS profile, check your air filter, use the OBD2 reader to check for STFT and MAF g/s at idle (for vacuum leak confirmation), use the OBD2 reader to check AFRs when it's accelerating that slow, see if it's hugely lean or hugely rich.
Old 12-17-2013 | 07:49 PM
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Damn thanks for the info. It wouldn't be the cat because I replaced it with a straight pipe and I replaced all the plugs wires and coils at the same time. But I flooded the engine 2 months back and it took forever to start ( I actually fried the starter) would this ruin the plugs wires coils?
Old 12-17-2013 | 07:53 PM
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First of all I see we have a know it all, like I said im on my 3rd rx8 and the best advice would be ask MAZDA,point blank and the period, before you go on his circus ride. Get the professionals advice, but at the end of the day asking is free and so was my engine courtesy of mazda. Boom.
Old 12-17-2013 | 08:16 PM
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Originally Posted by kennedy_RX8
Damn thanks for the info. It wouldn't be the cat because I replaced it with a straight pipe and I replaced all the plugs wires and coils at the same time. But I flooded the engine 2 months back and it took forever to start ( I actually fried the starter) would this ruin the plugs wires coils?
Good, no cat.

Yes, flooding tends to foul up the plugs, and this could be crippling your coils as a result too. But rather than just randomly replacing them, check mode 6 with an OBD2 reader to see your misfire count. If you aren't misfiring, then this is going to be a lean/rich problem (probably far too lean), but could be another problem like valve actuation (which could be choking off your intake flow as a result)

Is there any point in the rev range in any gear that the engine behaves normally?

Originally Posted by coderedalert
First of all I see we have a know it all, like I said im on my 3rd rx8 and the best advice would be ask MAZDA,point blank and the period, before you go on his circus ride. Get the professionals advice, but at the end of the day asking is free and so was my engine courtesy of mazda. Boom.
The problem is that anyone who has actually done that finds that in the vast majority of cases Mazda techs have no idea wtf they are doing with a rotary. Your post about "the codes" being the problem with a 2004 shows that while it may be your 3rd rotary, you still aren't any more knowledgeable. The problem with 2004s off the boat was a flash problem that had nothing to do with codes, and it had nothing to do with fuel injection. It was entirely around oil injection, the OMP rates were far too low. This was fixed with MSP16, and even if it wasn't fixed, the resulting problems from low OMP rates isn't the symptoms he is describing. The only significant flash change around fueling was for the start-up fuel maps, it leaned them out more and held off on increasing the fuel rates to normal cold levels until after the engine was running for a period, to help reduce the chances of a flood. It has nothing to do with running in gear at speed.

There were also no recalls for engine loss of power. TSB, yes, not recalls. Very different things. Since he has a 2004, he won't be under any warranty period, so going to Mazda for anything, even a TSB, will just be making him pay through the nose unnecessarily.

Last edited by RIWWP; 12-17-2013 at 08:23 PM.
Old 12-17-2013 | 08:41 PM
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I hope mazda works with you Kennedy, good luck, despite the quirks I have yet to run into a certified mazda mechanic who didn't know what to do, and please follow up with Mazda USA.


Mazda To Recall EVERY RX8 Ever Made!!





https://www.rx8club.com/attachment.p...8&d=1272304028

http://www.google.com/url?sa=t&sourc...9d2nP5UbxeAmJw

Last edited by coderedalert; 12-17-2013 at 08:52 PM. Reason: new information
Old 12-17-2013 | 08:45 PM
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Oh, wow....a forum post that is also incorrect.

Here is a list of all Mazda recalls since the late 70s/80s. I bolded the only 5 RX-8 recalls.

RECALLS
6812G - 2001-2008 Tribute 3.0L Engine Cover Modification Voluntary Safety Recall

6712A - 2001-2002 Tribute ABS Relay Installation and Master Cylinder Reservoir Cap Replacement Voluntary Safety Recall

6511K - 2012 Mazda3 Variable Valve Timing System Voluntary Emission Recall Campaign

6611K - 2010 CX-7 and 2010 Mazda6 Readiness Code For Evaporative Monitoring System Emissions Recall

6411F - 2008-2009 MAZDA3 and MAZDASPEED3 Windshield Wiper Motor Voluntary Safety Recall

6211B - 2009-2010 Mazda6 2.5L Engine Fuel Tank Safety and Emission Recall

6110K - 2009-2010 Mazda5 Fuel Pump Connector Voluntary Safety and Emission Recall

6010H - 2007-2009 Mazda3 and Mazda5 Power Steering Voluntary Safety Recall

5810B - 2010 CX-9 Seat Warmer Voluntary Safety Recall

5709J - 1995-1997, 2001-2003 B-Series Cruise Control Deactivation Switch Recall

5509E - 2009 Mazda3 Dynamic Stability Control (DSC) Safety Recall

5409D - 2010 Mazda3 Emission Harness Voluntary Safety Recall

5309B - 2007-2009 CX-9 Power Adjustable Driver's Seat Voluntary Safety Recall

5209A - 2009 Mazda6 Outer Door Handle Voluntary Safety Recall

5109A - 2009 B-Series 4X2 Front Spindle Voluntary Safety Recall

5008H - 2007-2008 MAZDA6 (Cal. Spec. Only) - Metal Fuel Tank Coating Recall

4907H - 2007 CX-7, 2007 Mazdaspeed3, 2006-2007 Mazdaspeed6, and 2006 Mazda6 OBD-II Compliance - Voluntary Emission Recall

4807H - 2007 CX-7, 2007 Mazdaspeed3, and 2006-2007 Mazdaspeed6 MIL Illumination (DTC P2006) - Voluntary Emission Recall

4707H - 1998-2002 B-Series Cruise Control Deactivation Switch Recall

4607F - 2007 Mazdaspeed3 Engine Mount Bolt - Safety Recall

4507C - 2001-2004 Tribute Anti-Lock Brake System - Voluntary Safety Recall

4407B - 2007 Mazdaspeed3 Genuine Mazda Accessory All-Weather Floor Mat Recall

4306K / SSP68 - 2006 Mazda5 Sliding Door Latch - Recall

4206F - 2004-2006 RX-8 Reprogram PCM - Voluntary Emission Recall

4106E - 2006 Mazdaspeed6 Lack of Power - Voluntary Emission Recall

4006D - 2005 Tribute Headliner Compliance Recall

3906C - 2006 Miata Air Bag Recall

3705K - 2006 B-Series and 2006 Tribute Windshield Wiper Motor - Recall

3605J - 2006 Mazda5 Heat Damage Around Main Silencer Recall

3505H - 2001-2002 Miata Emission Failure Recall

3405G - 2004 RX-8 Front Lower Arm Ball Joint Recall

3305G - 2004-2005 RX-8 Thermal Damage Recall

3205G - 2004 Mazda6 3.0L Evaporative Circuit Failure Emission Recall

3105G - 2004 Mazda6 "O2" Sensor Failure No Illumination Recall

3005C - 2003 Protege Intake Manifold and Variable Tumble Control Valves Emission Recall

2804L - 2004-2005 Tribute Lift Gate Recall

2704L - 2002-2004 Tribute Accelerator Cable Recall

2604L - 2004 Mazda6 Rear Seat Belt Recall

2304J - 2004 Mazda3 Crash Zone Sensor Recall

2204H - 2002-2003 MPV PCV Hose Emission Recall

2104F - 2004 MPV FMVSS Certification Label Recall

2004F - 2000-2001 MPV Actuator Cable Recall

1904D - 2001-2003 Tribute Powertrain Control Module Re-Calibration - Recall

1704B - 2004 RX-8 Manual Transmission Dynamic Damper - Recall

1604B - 2004 MPV and 2004 RX-8 Front Passenger Side Airbag Recall

1503L - 2001 Tribute Seat Belt Cover Replacement Recall

1403L - 2003 Mazda6 Fuel Odor Recall

1303F - 2003 Mazda6 Check Engine Light Emission Recall

1203F - 2003 Mazda6 Brake Reservoir Recall

1103F - 2002-2003 MPV, 2001-2003 Miata, and 2003 Mazda6 Fog Lights Recall

1003E - 2003 Miata PCM Replacement Recall

0903C - 2002-2003 MPV Front Fog Lights Recall

0802H - 2001 MPV Passenger-Side Air Bag Module Recall

0702F - 1999 - 2000 Protege Ignition Coil - Emission Recall

0602D - 2002 MPV Certification Label - Recall

0502A - 2000-2001 MPV DX Brakeline Proportioning Valve Replacement Recall

0401H - 2001 B-Series Seatbelt Buckle Recall

0301B - 2000-2001 Protege Left Side Rear Flexible Brake Hose Recall

0100L - 1993-1995 RX-7 with Mazdaspeed Carbon Fiber Hood - Recall

99011 - 2001 Tribute Owner’s Manual Correction Child Restraint Anchorage System Instructions Recall

98011 - 1999 Protegé with FMS Audio Rear Speaker Recall

97010 - 2001 Tribute Fuel Leak Recall

96009 - 2001 Tribute Incorrect Rear Wheel Hub Installation Recall

95010 - 2000 B-Series Front Passenger Side Seat Belt Buckle Recall

94009 - 2001 Tribute Steering Wheel Mounting Nut Damage Recall

93008 - 2001 Tribute Cruise Control Cable Cap Damage Recall

92007 - 1998 626 2.0L Engine Timing Belt Tensioner Recall

91007 - 1995-1996 Protégé Headlight Switch Recall

90006 - 2000 MPV Tire Labels Recall

89004 - 1999-2000 626 Brake Master Cylinder Cap Recall

88004 - 1999 Miata Hard to Refuel Recall

87004 - 1994 626/MX-6 Headlight Switch - Recall

86003 - 2000 MPV Reprogramming of the Powertrain Control Module (PCM) - Recall

85001 - 1993-1994 Navajo Liftgate Bracket Reinforcement Recall

83910 - 1995 626 Emissions Recall

82907 - 2000 MPV Door Lock Recall

80906 - 1998-1999 B-Series Cruise Control Cable Recall

77810 - 1998 626 Radio Recall

75804 - 1999 Miata Fuel Injector Recall

73801 - 1998 626 PCM Recall

72803 - 1990-1994 323, 1992-2993 MX-3, 1990-1993 Protege - Automatic Shoulder Belt Recall Campaign and Door Latch Switch SSP

70709 - 1992-1995 MX-3 Front Coil Spring Recall

68702 - 1989-91 RX-7 Automatic Shoulder Belt Recall

65609 - 1993-95 RX-7 Brake Vacuum Hose Recall

64603 - 1994 BSeries and 1991-94 Navajo Brake Booster Replacement Recall

63602 - 1994 B2300 Throttle Icing at Highway Speeds Recall

61510 - 1992-93 Navajo Liftgate Bracket Reinforcement Recall

60504 - 1993-94 RX-7 Fuel Leakage Recall

59503 - 1995 Protege Engine Valve Spring Recall

58502 - 1995 626 Passenger Side Air Bag Recall

57409 - 1994 B-Series and 1993-94 Navajo Parking Brake "Skip" Thru Recall

55406 - 1991 B3000 and B4000 Front Fuel Line Assembly Recall

53404 - 1988-91 626 and 1988-89 929 Outer Door Handle Recall

49301 - 1991-92 B-Series White Steel Spoke Wheels Recall

47206 - 1990-91 626/MX-6 Turbo EGR Valve Recall

46204 - 1993 MX-6 Lower Ball Joint Retaining Bolts Recall

45206 - 1990 Miata Catalytic Converter Recall

44205 - 1990-91 MPV Rear Brake Shoe Recall

43202 - 1991 Navajo Rolling In Park Position Recall

42110 - 1989 MPV Brake Lock-Up Recall

41106 - 1991 MX-5 Miata ABS (Anti-Lock Brake System) Recall

39103 / 40103 - 1991 Navajo Fuel Tank Heat Shield and Rear Bumper Reinforcement Recall

38101 - 1989 MPV Brake Vacuum Hose Recall

34006 - 1986-87 626 Ignition Switch Recall

32903 - 1985 RX-7 Exhaust Emission Control System Recall

31805 - 1988 626 Automatic Shoulder Belt Recall

30803 - 1988 626/MX-6 Throttle Valve Frosting Recall

29802 - 1988 929 Evaporative Emission Recall

27801 and 28801 - 1988 626/MX-6 Fuel Fixing Band and Rear Drum Brakes Recall

26801 - 1986 - 87 RX-7 Front Brake Recall

25711 - 1986 RX-7 Exhaust Emission Recall

22702 - 1982 GLC Exhaust Emission Recall

21605 - 1982 RX-7 Evaporative Emission Control System - Recall

20604 - 1986 626 Evaporative Emission Control System - Recall

19604 - 1986 626 Throttle Sensor Campaign - Recall

18601 - 1982 GLC Cruise Control Recall

17510 - 1977-83 GLC, 1979-82 626 and 1979-83 RX-7 Recall

15410 - 1981-82 GLC Recall

14410 - 1981-82 626 Recall

13305 - 1978-83 GLC and 1979-82 626 Recall

11012 - 1981 RX-7 Recall

This is a direct copy and paste from Mazda's service information site, the ENTIRE recall history for Mazda, regardless of model.

And yeah, I've read the detailed information on each. None of them were an engine recall.

The only 2 involving the engine:
4206F - 2004-2006 RX-8 Reprogram PCM - Voluntary Emission Recall:
Mazda Motor Corporation has decided to conduct an Emission Recall Campaign to reprogram the Powertrain Control Module (PCM) and replace the spark plugs on certain 2004-2006 RX-8 vehicles produced from April 10, 2003 through June 1, 2006. If you are a recipient of this notice, your vehicle is included in this recall.
What is the problem?
Due to PCM software calibration issues, the following conditions may result:
i) The oil-injection metering system may be inaccurate causing poor engine sealing of the combustion chambers resulting in drivability or emissions problems.
ii) Too much fuel may be injected at the time of engine start causing carbon to be deposited on spark plugs or plugs may be flooded, causing a difficult start condition. In addition, the catalytic converter may be degraded on some vehicles.
iii) (Only 2006 RX-8 vehicles are affected.) A test value indicating engine coolant temperature may be incorrectly shown on the service tool when a diagnostic function test is performed at dealership.
3305G - 2004-2005 RX-8 Thermal Damage Recall
Mazda Motor Corporation has decided that a defect, which relates to motor vehicle safety, exists
in certain 2004-2005 RX-8 vehicles produced from April 10, 2003 through July 7, 2005.
If you are a recipient of this notice, your vehicle is included in this campaign.
What is the problem?
On certain 2004-2005 RX-8 vehicles, if a RX-8 is parked and the engine is operated at high
RPMs, excessive heat build-up may affect oxygen sensors, the neutral switch and back up
lights causing MIL illumination, and exhaust emission and drivability will be adversely affected.
It may also lead to problems with the parking brake cable tube causing loss of parking brake
function, malfunctions of the gas gauge and possible damage to the fuel tank causing fuel
leaks. Fuel leakage in sufficient quantity in the presence of an ignition source could potentially
result in a vehicle fire.


Soo...try again.
Old 12-17-2013 | 08:51 PM
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Yeah say I get my rpms up to 4500 and let off the gas then get on the gas again it runs great. I'll try to get it read tomorrow and I'll let you know. Thank you so much for this help!
Old 12-17-2013 | 08:54 PM
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Hey you missed some lol
Old 12-17-2013 | 09:00 PM
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Originally Posted by kennedy_RX8
Yeah say I get my rpms up to 4500 and let off the gas then get on the gas again it runs great. I'll try to get it read tomorrow and I'll let you know. Thank you so much for this help!
Ok, that would point toward something working itself out, like a stuck intake valve that gets another solenoid hit, or a failing MAF that sees the sudden change in airflow and manages to struggle back to life. Likely not an O2 problem since it's happening at full throttle.

See if you can get the MAF g/s at idle, short term fuel trim at idle, MAF g/s at full throttle when you are having the huge lag vs when you aren't at the same RPM, the AFRs in both conditions as well.

Originally Posted by coderedalert
Hey you missed some lol
The first link you posted is a TSB, NOT a recall. Big difference. Recalls are always covered by Mazda and never expire, TSBs are just instruction sets and if there isn't an available warranty on the car that covers it (most are bumper to bumper) than they can still do it but it's out of your pocket.

The 2nd link you posted is also NOT a recall, it is an extension of the original factory warranty on the powertrain for the engine and core components only to a new longer expiration point.

Last edited by RIWWP; 12-17-2013 at 09:02 PM.
Old 12-17-2013 | 09:10 PM
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ok im not trying to sound stupid but I have no idea how to do that lol im still trying to learn everything about the car
Old 12-17-2013 | 09:18 PM
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Hop onto Amazon.com and grab a cheap bluetooth OBD2 adapter. When you get it, download an available OBD2 app for your smartphone (Torque is the best for Android, and the $5 paid price is completely worth it, though the free version is all you need here. I don't know what iPhone apps are out there, but I bet there are a few).

Plug in the OBD2 adapter into the OBD2 port, pair it with your phone over bluetooth, then fire up the app. Within ~15 seconds you will have a live data stream from your ECU to your phone (or tablet or whatever). Start up the car and let it warm up and stabilize on the idle. Then pull up the live data section and add a gauge for MAF and a gauge for Short Term Fuel Trim. At idle, the short term fuel trim should be -1%, 0%, or +1%. If it is +4% or more and holding there, there is something wrong. If the MAF data is less than ~5g/s (5.5g/s is normal) as well, then you have a vacuum leak. 4.5g/s with +5% STFT is common for a small vacuum leak

Then and another 2 gauges, actual AFR and commanded AFR. Take the car for a drive, you might need someone else to hold the phone and read it to be safe, but i'll leave that up to you (I use a tablet stand bolted to the passenger seat rail). Get the power loss problem going and check the two AFRs and the MAF data. Bounce the revs around to clear up the problem and check them again. If your actual AFR is dramatically different than commanded AFR, then there is definitely a problem, though what might depend on the details of what you see. If the MAF airflow should be wildly different, but it's another data point that would help. If the STFT doesn't zero out at full throttle, then it would also indicate a problem.

Return back with the information that you are seeing and we should be able to get you pointed in a good direction.



Edit: You are on the opposite side of PA from me, or else I'd just invite you over to use my adapter and see what we could figure out in-person.
Old 12-17-2013 | 09:24 PM
  #24  
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ok ill do that....im sure ill have more questions so I added you to my contacts. Thank you so much its finally nice o have someone that knows whats going on ive been looking for like 2 months now
Old 12-21-2013 | 06:23 PM
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Ok idk if I did this right but my MAF is at like 5.5 and the fuel trim was at -0.8 and when it was having the lagging problem it was at the same number. When I'd get past the lagging part it would go to 0.0 I don't know of this would help I wasn't sure how to work the app


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