High INT and BLMs at idle

[Esasky's85GN]

Gents,

Decided to fire up the car tonight and let her run for a little while. After about 10 minutes, my INT was bouncing between 144 and 153... Yeah, 153. The BLM was sitting @ 142.

As soon as I snap the throttle, BLMs go to 130.

Car seems to be running good. Looked at my fuel pressure. Its sitting at like 36-37 PSI with vacuum line on. Didn't know if FP was a little low or not. I thin I may have my MAF translator set to 10% lean at idle but I didn't get a chance to check it.

As far as I know, I don't have any exhaust leaks or intake leaks.

Anything else I can check?

Thanks guys!

Chris

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[we4Mateo]

You can try adjusting the translator for the idle setting, but you may have a vacuum leak if the setting was all good before and now isn't with all else being equal. The vacuum leak will make the ecm think the engine is lean and add fuel like you are seeing.

 

[Esasky's85GN]

We4,

I am going to double check the translator setting. I had an old chip in the car and replaced it with a TT chip. Old chip was giving me low BLMs, now I am high.

W/B shows AFRs between 14.3 15.0 at idle.

U think 35-36 PSI with line on is too low?



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[we4Mateo]

...U think 35-36 PSI with line on is too low?



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No. Pull the vacuum line and it'll probably jump to 40-45psi. I would check it to be sure and set it for the chip you have; I believe TT chips are 43psi line off with gas.

 

[Esasky's85GN]

Will double check the FP and translator setting.

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[forcefed3.8's]

I wouldn't get too hung up on idle BLMs as long as there is no vacuum leaks, good O2 sensor, and AFR is in check. Verify line off pressure, and adjust the translator idle % (I think it works with the TT chips).

 

[TurboDave]

1. Well, first of all, just starting the car up and letting it run for 10 minutes or so is NOT a good way to monitor INT or BLM numbers at idle. If you want to see what they truely are, you have get the car out for a few miles of stop and go traffic, and then monitor what those numbers are at idle.
The INT and BLM seldom settle into what we like to see as "good" numbers just by warming up in the driveway.

2. If you're concerned about fuel pressure at idle, don't measure it with the vacuum line on. Oh, and when you do pull the vacuum line off, plug it so it doesn't skew your BLM higher.

3. Your wideband is telling you all is fine. The INT and BLM are doing their jobs.

4. The reason the number changed when you blipped the throttle is because you caused it to read and entirely different cell. There are MORE than one.

 

[626gn]

My BLM's came down when I changed my PCV valve while troubleshooting a smoking problem...