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Old 09-05-2013, 01:34 AM   #1
C10_ustacould
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No signal from MAF

My 5.3 developed sort of a hiccup on the way to work tonight. I just reconfigured the air intake, but I don't think it changed the positioning of the MAF sensor much. I have a reading of 0.2 lb/min almost all of the time, idle or 3000 rpm and occasionally spikes to 60+ lb/min then back to 0.2 lb/min. If the MAF is dead why does the engine still run? Is it dangerous to drive it much with out it? I found some values to check for on the harness, but the wiring seem to be in good repair. I have never really paid much attention and this issue has made me curious. What type of readings do you all get at idle and at cruising rpm?
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Old 09-05-2013, 09:11 AM   #2
C10_ustacould
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Re: No signal from MAF

Well, the MAF seems to be working. I pulled the fuse and reinserted it, not sure if that sent helped it or not, but the stumble is still there intermittently. I am going to move the MAF back to the TB to see if it clears up. If not, I'm going to check fuel pressure just to make sure its good. Just got off work so I'm going to take a nap first!
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Old 09-05-2013, 01:49 PM   #3
BR3W CITY
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Re: No signal from MAF

Engine can run without half of its sensors (o2 maf, tps, etc) but it won't run correctly throughout the table, nor will it drive the same when things like DBW are involved.

Could be the MAF is really dirty, especially if you've oiled the air filter and put the MAF very close behind. A little MAF spray can clean it up, as well as looking at the position and clocking of your MAF . It should sit upright between 10 and 2 if u think about it like a watch.
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Old 09-05-2013, 02:50 PM   #4
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Re: No signal from MAF

I had the same problem on my truck too. It was idling around 300 RPM and would die at stoplights randomly. The MAF was a little dirty, but not bad cleaned it anyway. Also pulled off the throttle body and there was bunch of gunk on the backside that was interfering with the sensor somehow, so I cleaned that up really good. Also put a new o-ring on the canister purge valve, made sure it was sealed tight. I did that about a year ago and the truck still runs good.

Also the truck will run without it, but will run like crap. Hope this helps!
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Old 09-05-2013, 05:53 PM   #5
C10_ustacould
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Re: No signal from MAF

I put the MAF directly on the throttle body and all symptoms went away. Now I need to rethink the layout of my CAI... One thing that limits my options is the length of the pig tail for the MAF, I may have to ask the guys at PSI to make me an extension.
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Old 09-05-2013, 07:27 PM   #6
Billett
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Re: No signal from MAF

Might be able to find the plugs at eficonnection.com and make your own for cheaper.
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Old 09-05-2013, 07:46 PM   #7
C10_ustacould
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Re: No signal from MAF

Quote:
Originally Posted by Billett View Post
Might be able to find the plugs at eficonnection.com and make your own for cheaper.
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I'll take a look, thanks for the link.
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Old 09-05-2013, 11:44 PM   #8
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Re: No signal from MAF

You could also cut the wire and solder and shrink tube longer pieces in and done. That worked for me when I rewired my engine harness.
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Old 09-06-2013, 01:01 AM   #9
BR3W CITY
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Re: No signal from MAF

don't solder anywhere close to the maf if you can avoid it. While many sensors can handle the external heat from the engine, its good to avoid heat INTO the sensor. It also helps to match the wire size and not go smaller to avoid heating or breaking the wires (not as big a threat on .5v and other ultra low voltage components)
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