Help!!

[TurboBuRick]

Throwing a ce light? What the code?

 

[Steve87GN]

Yes, code 45.

 

[NorCalTurbos]

Anyone? Anyone? Bueller?

Exhaust leaks hurt definitely pre turbo leaks. Get it welded up soon you'll notice a big difference. The o2 sensor detects more oxygen in your exhaust and it's telling the ecu to add fuel= rich condition.
What's you o2mv reading and the a/f numbers?

 

[TurboBuRick]

Exhaust leaks hurt definitely pre turbo leaks. Get it welded up soon you'll notice a big difference. The o2 sensor detects more oxygen in your exhaust and it's telling the ecu to add fuel= rich condition.
What's you o2mv reading and the a/f numbers?

If the o2 is reading lean its not going to throw a rich code.


Typical causes for code 45 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

 

[Steve87GN]

Thanks guys. So, I did find that post on gnttype.org. Just replaced the O2, fuel pressure holds at 40 when idling and spikes under throttle, fuel pressure stayed at 37 when I shut the car off and kept for 15 min. and even started increasing, running Kirban plug wires which tested between 9600 and 14000 ohms of resistance. I've got a new EGR valve, TPS sensor and MAF sensor waiting to be picked up. Anything I can check for the EVAP system?

 

[TurboBuRick]

Are you reading fuel pressure with a liquid filled rail mounted gauge? Those things will give erratic readings depending on temp. Radiant heat from the engine will lower reading. May explain why fp rises when left to sit with engine off.

Fuel would have to saturate the evap canister to make the tune rich. In that case you would smell raw fuel.

At this point I would say the chip or the mass air flow is the culprit. A high maf signal will make the tune rich.

I would be looking into a lt1 maf with a translator and a new chip but not before verifying the maf signal is running high.

Did you get the scanmaster hooked up yet? Take note of AF reading at idle and post back.

Rick

 

[Steve87GN]

Thanks Rick. Still waiting on the ScanMaster to arrive. There is no chip at play, this is the stock tune. And, the FP was read with one of these:

https://www.summitracing.com/parts/hyp-4004

I'll post the readings from the ScanMaster once it arrives and I can get it hooked up.

 

[NorCalTurbos]

Did you ever switch out the maf? Since you are so close, if you need to you can borrow 1 I have 2 of them stock that are good 1 is brand new. Just a thought.

 

[Steve87GN]

Thanks man! I haven't yet. I have one from AutoZone to put on (Cardone), but haven't yet. Trying to control the parts I swap. But, it's probably not a bad idea anyways considering the age. Will swap today and let you guys know what the word is.

 

[earlbrown]

Thanks man! I haven't yet. I have one from AutoZone to put on (Cardone), but haven't yet.

When you're troubleshooting DON'T assume that new MAF is working correctly just because it's new. 15 years ago the magic number with parts store MAFs was ''12'' . In other words, it took 12 tries to get a mass air that would idle in the right range and hit 255 around 17 PSI. It has to be worse now.

In my personal case, it took exactly 12 tries to get one that made my car driveable.

Years later the Translator came out and I replaced my 'good' MAF with an LT1 unit. The car ran much much better in every aspect.

 

[Turbo Keith]

I battled around with a stock MAF sensor before I listen to the guys and got a LT1 and Translator . Car runs and idles so much better . I promise you will love that upgrade . How bout the Scanmaster ? You got it hooked up ?

 

[GNONYX]

Are you reading fuel pressure with a liquid filled rail mounted gauge? Those things will give erratic readings depending on temp. Radiant heat from the engine will lower reading. May explain why fp rises when left to sit with engine off.

Fuel would have to saturate the evap canister to make the tune rich. In that case you would smell raw fuel.

At this point I would say the chip or the mass air flow is the culprit. A high maf signal will make the tune rich.

I would be looking into a lt1 maf with a translator and a new chip but not before verifying the maf signal is running high.

Did you get the scanmaster hooked up yet? Take note of AF reading at idle and post back.

Rick

I'm not trying to stir up some crap, but are your referring to this one on Full Throttle, or another type?
http://www.fullthrottlespeed.com/tu...or/rail-mount-fuel-pressure-gauge-for-gm.html

 

[TurboBuRick]

I'm not trying to stir up some crap, but are your referring to this one on Full Throttle, or another type?
http://www.fullthrottlespeed.com/tu...or/rail-mount-fuel-pressure-gauge-for-gm.html

IMO Any liquid filled gauge will be effected by heat.

 

[earlbrown]

Not just your opinion, basic science.

You can't have an accurate PSIG relative to atmospheric pressure if the front doesn't have access to atmospheric pressure.


The hotter it gets, the lower it reads.

 

[Jerryl]

True on the gage accuracy.
Many believe is has to do with the liquid.
In reality, it is the delta pressure to baro due to the closed camber.

 

[GNONYX]

so what you're saying is to make the adjustment when the engine is hot and up to temperature?
Or don't rely on the fuel gauge, just place a Fuel Pressure Tester inline of the fuel rail and make the fuel adjustment?

 

[earlbrown]

No. What we refer to as 'PSI' is actually 'PSIG'. The ''G'' stands for gauge. The gauge reading is actually pressure above atmospheric.

For example, if you have exactly 30 PSI in your tires (per a gauge) and atmospheric pressure goes up one pound, you're pressure reading will change even though you have the exact same amount of air the the same space. That's why carbs have to change jets depending on pressure. Full pretty much stays the same size but oxygen density per cubit foot changes with weather.


Back to the fluid filled gauge... When you have a sealed cavity on the 'reference' side, it's no longer telling you how many pounds above atmospheric you are. It's not telling you how many pounds above the fluid cavity you are. And that pressure will increase as the gauge heats up.


If you could heat that fluid up to have 45 pounds of pressure on the face, your FP gauge would read zero at idle when you actually have 45PSI.

 

[GNONYX]

I understand what you're saying, but what I'm asking:
Is to make the adjustment when the engine is hot and up to temperature?
Or don't rely on the fuel gauge, just place a Fuel Pressure Tester inline of the fuel rail and make the fuel adjustment?

 

[earlbrown]

I'm saying, don't trust your life with a fluid filled gauge. They aren't accurate.

Engine temp and gauge temp aren't going to be the same. Not to mention those gauges aren't good gauges to start with.


It's like having a major brain injury then smoke crack. When you start out in deficit, then make it worse.....


...well, it's worse.

 

[Chuck Leeper]

Why the discussion on MAF sensors, O2 sensors, nasty plugs, when the OP has clearly stated the exh header is cracked so badly, he can hear it in the car?
Fix the obvious, then look for the "obscure"....