It may be time to get another electronic leak tester and I'm looking for what others use. The TIF 5500 I've used for years never seemed to really work right and now is worse. It will find a gross leak ( like loosening a charge hose ) but regular leaks are a challenge. Now getting non repeatable results, random beeping. Changed tip no real difference.

I have access to a ultrasonic leak tester that I might give a try, any luck with those or are they more suited to gross compressed air system leaks?.

My 97 C280 will drop pressure from 45 PSI to 40 in 5 minutes so it is a pretty large leak,( I just pump in a bit of gas not a full charge )

The 5500 has not been able to locate the source and semi randomly beeps near the compressor area , TXV and dash vents.

With such a large leak I'm tempted to make block off plugs and isolate areas of the system. I'd rather not use freon in enough quantity to make die work until I get the big leak fixed.

Thanks

I found a picture of the 1 I use as a pro. this is not a suggestion to buy the item from the site. been very good. like all leak detectors, it takes practice. if you buy a used 1, plan on spend 40-50 for the updated diode sensor they just introduced. I haven't done it yet because it JUST came out but have heard good things about the update from others. good luck, chuck.

I have tried a few cheaper sensors, and one that was about 150$ or so.

I now use soapy water, and if that doesn't catch it, uv dye and a black light.

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Eugene

10 E63 AMG
93 300te 4matic
07 BMW X3
14 Ford F-150 Fx2

I used my phone with a free amplifier app to find a leak at the dryer. Every leak will hiss and the phone's microphone will pick it up no matter how faint.

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CENSORED due to not family friendly words

Ended up getting a electronic sniffer leak tester TIF brand XP1A . This seemed to be the best balance of feature / costs. ( ~ $ 150 including shipping. )

It has the vital feature of 7 sensitivity levels and 18 graduations within each level. The audio function is too confusing for the moment. It has a rhythmic beep that is faster at higher sensitivity levels, when freon is sensed the beep turns to a siren sound. It is difficult to make a fine distinction between small changes in the beep / siren.

The visual bar display is much more useful, The 7 LED display starts out green, then orange then red to give the 18 levels. This allowed me so sweep the system at high sensitivity to find the general leak then less sensitive to locate actual leak.

Down sides of this device are: Made in China, plastic box requires the sensing wand to be nearly kinked for it to fit.

I tried the loaner ultrasonic leak tester but it was not too useful even though the leak was large. There was some sense that something is leaking there but I could not home in on it.

Leak turned out to be condenser corrosion directly behind the aux fan motors. This car was a CA car that made it's way to salt areas , back to CA. The car was never driven in enough rain to wash the area behind the fans. Finding this with bubbles would be difficult as the leak turned out to be between fins.