Won't stay running, any help would be appreciated.
#1
Won't stay running, any help would be appreciated.
Starting a new thread because the only thread I seen that had this same problem did not have a resolution.
i have a 05 Rx8 6 speed with 66,xxx miles
It starts fine but will not idle, will not rev unless I feather the gas. If I unplug the maf it will run a lot better but still won't idle and sputters some.
Things ive done so far:
New spark plugs
New ignition coils and wires,
New Maf
Checked for vacuum leaks and did not spot any
Cleaned the throttle body and intake
I will post a video with the maf plugged in so y'all can see exactly what it's doing.
i have a 05 Rx8 6 speed with 66,xxx miles
It starts fine but will not idle, will not rev unless I feather the gas. If I unplug the maf it will run a lot better but still won't idle and sputters some.
Things ive done so far:
New spark plugs
New ignition coils and wires,
New Maf
Checked for vacuum leaks and did not spot any
Cleaned the throttle body and intake
I will post a video with the maf plugged in so y'all can see exactly what it's doing.
#3
What am I doing here?
Join Date: Mar 2006
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What happened before this started?
Are there any other codes behind that check engine light in addition to the one for the disconnected MAF?
Have you cleaned your ESS and reset the ESS profile?
How did you search for vacuum leaks? Did you use a smoke machine? I know some people recommend spraying carb cleaner at various air connectors but there are so many that it would be easy to miss some. Did you make sure that the vacuum caps didn't rot off of the service nipples on the lower intake manifold?
If you don't have one, get a bluetooth OBD-II adapter and app for your phone. Tell us what the short term fuel trim and long term fuel trim look like. Also, tell us how much air flow the MAF is reporting.
Are there any other codes behind that check engine light in addition to the one for the disconnected MAF?
Have you cleaned your ESS and reset the ESS profile?
How did you search for vacuum leaks? Did you use a smoke machine? I know some people recommend spraying carb cleaner at various air connectors but there are so many that it would be easy to miss some. Did you make sure that the vacuum caps didn't rot off of the service nipples on the lower intake manifold?
If you don't have one, get a bluetooth OBD-II adapter and app for your phone. Tell us what the short term fuel trim and long term fuel trim look like. Also, tell us how much air flow the MAF is reporting.
#4
Thanks for the reply,
i bought it and it was already running like this, additional engine codes are misfire in cylinder 1, and system is too lean, i didn't clean the ess because it looks brand new but I will do that tomorrow. I have reset everything I know - pumping the brakes 20 times within 8 seconds, had the dsc light because the battery was bad when I purchased the car so I reset that. I sprayed carb cleaner at every location I seen that could possibly leak and it didn't show signs of a leak, I removed the upper intake to inspect the seals and they all look good, pulled all the vacuum hoses off to make sure they were not clogged, I just ordered a Bluetooth obd 2. I will post those results when it comes in. The service nipple caps looked good but I replaced them anyway just to be sure, I did add a new ground wire from the frame to the engine and it runs a lot better but still idles a little rough. I am still getting the system is too lean code and cylinder 1 misfire, I replaced the spark plugs, ignition coils and wires as soon as I got the car so I don't know why I'm still getting a misfire. It has a midpipe so that may be why I'm getting the code system is too lean? It looks like it was very well taken care of, starts right up every time cold or warm.
i bought it and it was already running like this, additional engine codes are misfire in cylinder 1, and system is too lean, i didn't clean the ess because it looks brand new but I will do that tomorrow. I have reset everything I know - pumping the brakes 20 times within 8 seconds, had the dsc light because the battery was bad when I purchased the car so I reset that. I sprayed carb cleaner at every location I seen that could possibly leak and it didn't show signs of a leak, I removed the upper intake to inspect the seals and they all look good, pulled all the vacuum hoses off to make sure they were not clogged, I just ordered a Bluetooth obd 2. I will post those results when it comes in. The service nipple caps looked good but I replaced them anyway just to be sure, I did add a new ground wire from the frame to the engine and it runs a lot better but still idles a little rough. I am still getting the system is too lean code and cylinder 1 misfire, I replaced the spark plugs, ignition coils and wires as soon as I got the car so I don't know why I'm still getting a misfire. It has a midpipe so that may be why I'm getting the code system is too lean? It looks like it was very well taken care of, starts right up every time cold or warm.
#5
What am I doing here?
Join Date: Mar 2006
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If you're getting misfire and lean codes you likely either have too much air or not enough fuel. A midpipe will not affect this. If you're running cat-less you should get a P0420 (catalyst below efficiency) code.
Step 1: stop running it until you get these sorted out. If your engine isn't already trashed, misfires will trash it.
Step 2: verify the lean code by looking at your fuel trims and MAF rate when your OBD2 adapter arrives. At warm idle, your MAF should be reporting between 4.5 and 5.5 g/s. Less than this indicates a vacuum leak. Fuel trims between -8% and +8% are no big deal. IIRC, you have to be up over +20% to throw a lean code.
Step 3: go over your intake and vacuum systems with a fine-tooth comb. If possible, get your hands on a machine to smoke test your intake. It makes finding leaks stupid easy. Read here for more info.
Step 4: Check your fuel pressure. A weak fuel pump may not be providing enough fuel which will cause the engine to run lean. You'll need a T-connector and a gauge and you may be able to rent this as a kit from an auto parts store. The fuel line connections are between the brake booster and the UIM.
Step 5: best of luck and godspeed.
Step 1: stop running it until you get these sorted out. If your engine isn't already trashed, misfires will trash it.
Step 2: verify the lean code by looking at your fuel trims and MAF rate when your OBD2 adapter arrives. At warm idle, your MAF should be reporting between 4.5 and 5.5 g/s. Less than this indicates a vacuum leak. Fuel trims between -8% and +8% are no big deal. IIRC, you have to be up over +20% to throw a lean code.
Step 3: go over your intake and vacuum systems with a fine-tooth comb. If possible, get your hands on a machine to smoke test your intake. It makes finding leaks stupid easy. Read here for more info.
Step 4: Check your fuel pressure. A weak fuel pump may not be providing enough fuel which will cause the engine to run lean. You'll need a T-connector and a gauge and you may be able to rent this as a kit from an auto parts store. The fuel line connections are between the brake booster and the UIM.
Step 5: best of luck and godspeed.
The following users liked this post:
gwilliams6 (11-15-2017)
#9
Okay I will check all vacuum lines again tomorrow, I will try to get a smoke machine to test with. How would I test with a smoke machine and is there anything else that could be causing this problem?
#10
Another thing I've noticed is the cel will go off shortly and it will come back on and every time it is the same codes, sometimes the cylinder misfire 1 code will not be there.
#11
What am I doing here?
Join Date: Mar 2006
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Here's a good resource on how to smoke your intake.
Misfire events don't always trigger a persistent code even if they cause a flashing CEL.
Misfire events don't always trigger a persistent code even if they cause a flashing CEL.
#12
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It can be more than vacuum lines, too. For instance, my vacuum leak that threw LTFTs that high was caused by one of the SSV bolts being loose (I broke the first one and was too loose on the replacement ). Also verify all of your gaskets on the upper intake manifold are in good shape, no pinches or breaks.
#13
Alright thanks for the info. I will be home in an hour and I'll take the upper and lower intake off along with all the vacuum lines to make sure they are in good condition and going to the right places. I'll post an update as soon as I get done to let y'all know what the results are.
#14
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Alright thanks for the info. I will be home in an hour and I'll take the upper and lower intake off along with all the vacuum lines to make sure they are in good condition and going to the right places. I'll post an update as soon as I get done to let y'all know what the results are.
#19
Don't know if that would be the cause of this, mine doesn't but everything looks good, I've got the upper intake off as we speak, all the gaskets look good, one of the bigger hoses that connects to before the throttle body on the intake goes to the omp, one goes to the oil refill and the other one goes where?
#20
What am I doing here?
Join Date: Mar 2006
Location: 2017 Miata RF Launch Edition
Posts: 3,606
Received 649 Likes
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Don't know if that would be the cause of this, mine doesn't but everything looks good, I've got the upper intake off as we speak, all the gaskets look good, one of the bigger hoses that connects to before the throttle body on the intake goes to the omp, one goes to the oil refill and the other one goes where?
#23
Ltft-1.8 ~ 3.7
Maf 4.75 ~ 5.45
After I reinstalled the upper intake and throttle body I installed the aftermarket intake that was on the car when I bought it and it still didn't fix anything so I took the air filter off to clean it and I noticed whoever installed it before I got it pushed it as far up on the tube as it would go so it wasn't getting much air at all through it so I went and bought another filter and installed it properly. Bam runs like charm
Maf 4.75 ~ 5.45
After I reinstalled the upper intake and throttle body I installed the aftermarket intake that was on the car when I bought it and it still didn't fix anything so I took the air filter off to clean it and I noticed whoever installed it before I got it pushed it as far up on the tube as it would go so it wasn't getting much air at all through it so I went and bought another filter and installed it properly. Bam runs like charm