code 45

[86grandnat.]

I just pulled the car outta the garage today to get her all cleaned up and i noticed on start up it appeared to be running a little rich (could smell gas in exhuast). Now, I went out to put it back in the garage and it started fine, but was burning incredibly rich and I noticed the check engine light was on. I shut the car off and did the "paperclip" test and a code 45 comes up. Thats the only code I have. I was wondering, could leaky exhuast manifolds cause it too run extremly rich, cause both sides of my manifolds have a least 2 noticable cracks in them. I have new exhuast manifolds but I haven't had time to put them in. The O2 sensor was replaced last year. I don't have a scanmaster, I was going to get one, but this car is costing me soo much money I can't afford it! Any help is greatly appreciated, thanks!

 

[jays87gn]

CODE 45

Trouble Code 45 indicates that the O2 sensor is showing a persistently low exhaust oxygen content (rich), despite the efforts of the ECM to decrease injector on-time (thus decreasing fuel delivered). Integrator and BLM numbers may indicate < 128 by a substantial margin.

The conditions for setting this code are:

no Code 34 or Code 35 (MAF error) present, and
the O2 sensor voltage remains above 752 mV, and
the ECM is in Closed Loop control, and
throttle position is < 2 percent or > 20 percent, and
the above conditions exist for more than 20 seconds.

Typical causes for this code include:

1) O2 sensor defective or contaminated (if incorrect RTV sealant or too much RTV is used, this may happen)
2) Leaking fuel injectors
3) Fuel pressure too high
4) EMI interference from poor plug wires
5) Evaporative Emission system defect
6) TPS and/or EGR problem
7) MAF sensor reading higher airflow than is actually present

It's Most likely the maf tap on it with a screwdriver and see if it stumbles

 

[86grandnat.]

Ok, I started the car today after work and let it run for a couple mins. I did the tapping on the maf like you said and everytime I hit it, the car stumbles like you said. So, does this mean the mass air flow sensor is wrecked?? If so, where would I go to get a new one, cause i am in a hurry to get this car running! Does GM still carry these or am I goin to have to go aftermarket? Thanks for the help thus far!

 

[jays87gn]

It sounds like you need a new maf gm discontinued them you can still get a reman from any parts store but I highly suggest you get a maf translator and upgrade to the newer maf the reman ones are junk.

 

[86grandnat.]

Ok, what is a maf translator? What new maf sensor would u recommend me getting? I red about LT1, LS1 maf's, but I don't clearly understand whats all involved with them. I just wanna get this car running good again cause I plan on selling it real soon! Where would be the best place to get the translator and new maf?? I am still using the stock air box and hoses. Thanks!

 

[jays87gn]

Click for Translator

Click for 3" Maf Sensor From Impala SS

hope that helps

 

[86grandnat.]

Thanks man, so that is everything I am going to need to do the conversion?? Like, the stock hoses will still bolt to that maf sensor? Does that translator just plug right into you factory unit?? I was just wondering, I started the car again, did the tap thing and it would only sputter once in a while. I can tell its running like crap, cause the exhuast just smells like gas really bad and the car is popping at idle. I reset the engine light and ran that car again and about 5 mins later the light came on indicating code 45. I unplugged the maf, the engine light came on right away the it showed codes 34, 45. The car ran the same with the maf unplugged. But, if this sounds like the maf sensor, i better change it, really wishing I wouldn't have to pour any more money into this car.

 

[salvageV6]

Assuming it's a new car to you, it could be the injectors and chip combination.

What are they?

I'd get a Scanmaster ASAP for important diagnostics.

 

[86grandnat.]

I bought the car a year ago but have only put about 5000 miles on it so far. The car has ran perfectly fine till now. The guy I bought it off of had the injectors changed when he rebuilt the motor 10 years ago and the chip had been in the car for at least 5 years from what he said. The injectors are one step up from the stock ones, not sure what kind of chip it is. I still have the stock chip and another chip (not sure what kind it is). I was goin to buy a scanmaster but I never had enough money to get one, and now that I plan on selling the car I really don't want to put any more money into it unless I absoluty have too. Thanks!

 

[86grandnat.]

So, is that all I am goin to need to put that maf in. I will get the translator and the impala ss 3" maf. Are these just pretty much plug into factory then your good to go?? Thanks!

 

[jays87gn]

yep the maf is pretty much plug and play but I would also check out the other things to make sure its the maf before replacing or try a known good maf and see how that works

 

[86grandnat.]

Well, I already ordered a LT1 maf, translator, and a o2 sensor just in case that is bad too. I would try another maf but there is no-one around here I know that has a grand national, t-type that I could use one off of. I kinda live out in the boonies. How long does it usually take for the order to go through with full throttle speed, cause I ordered the parts a couple days ago and they still haven't taken payment off my mastercard yet?? What else do you suggest I do, the plugs n wires are brand new about 2000 miles ago, air filter is brand new. I could slap the factory chip in I guess and see how that runs. When I had the fp checked last year it was set at 42psi line off. The car ran really good till now, well, it was kinda flooding itself when I would start it before, but never this bad to bring a check engine light on. Once it would get warm though, it ran pretty much perfect, cept for my smokin turbo. Thanks for the help so far!