2008 Honda Fit M/T

Recently I have been having issues where my AC won't cool down on hots days. Noticed it first when I was stuck in traffic in the desert coming from Las Vegas back to LA. The symptoms were that it will not get cold unless I was moving at a good pace.

When I checked the condenser, the fins were heavily bent all over and I ended up replacing the condenser and then also replaced the condenser fan a week later since I noticed that it was not turning on.

The AC system was recharged by my friend who is a HVAC technician. Unfortunately, he doesn't work on cars so he was out of ideas as to why my AC would stop working.

I am starting to notice that the engine bay get's quite hot after a ride and I do not remember it being so hot before whenever I opened up the engine bay. I am thinking that the heat that is trapped in the engine bay may possibly causing the AC compressor to stop working to protect it from the heat.

Coolant levels are good, engine oil levels are good, no bubbles in the coolant (I think), no loss of fluids, no engine overheat signs on the dash, OBD2 scan tool reads the coolant temperature at 176 ~ 178 constantly while driving, and I'm out of ideas.

I'm not sure if the heat from the engine / engine bay is causing the AC compressor to stop working or if it's a completely different issue.

If there is anybody on this forum good with AC work, here are the readings that I got on the gauge recently. One is when the AC was actually working and the other is when it stopped.


A/C Working



A/C Not Working

Any tips, suggestions, or ideas are greatly appreciated and will give them a shot. I would like some way to compare my engine bay heat to another user here but I'm not sure how that can be accurately accomplished.

 

I was not able to see the pictures but the pressures in psi should be : high side 2 times ambient temp in F + relative humidity (with ambient temps below 110 F)
low side 27 to 33 psi
The data should be recorded with engine running at 1500 rpm (important) not on 900 rpm
fan on high, selector on vents
the a/c cycles every 25-30 seconds at 80 F outside (recirc).
The E28 terminal on ecu is for a/c signal.
With a/c s/w on and blower fan on 2 the voltage between this terminal and the ground should be close to 0 even if clutch is not engaged (cycled off).
The current flows between E28 and a ground as follows:
E28 main ECU> overtemp s/w on compressior body (NC)> hi/lo pressure switch (NC)>a/c main s/w> speed selector>ground. If any of these switches are open the a/c will not run (E28 to ground will be about 5 volts)
Is green LED on when you are pushing a/c main s/w in? If not,
Historically, the a/c switch is defective on some models; this causes a fuse 10 (7.5 A) for a/c (under dash box)to blow leaving the car without a/c and without fans.

 

High side reading is more than double it seems. Ambient temp that day was 103F during the time of reading.

Readings were taken while revving at 1500RPM but I forget if the fan was on high or not. The AC works perfectly fine during the night or whenever the outside temperature is rather cool, which makes me believe that it is not a faulty AC switch. The AC light is always on even when the AC is not working properly.

 

If so the low side reads 55 to 65?(again I don't see the pictures
the system is either overcharged or have an air trapped inside. The a/c guy must vacuum the system for 30 minutes with 29 " of mercury vacuum before charging. I hope the system has proper amount of oil now.
The undercharged system actually cools better at high temperature low humidity ambient and cools poorly with ambient 80 f

 

On the picture I took, it shows about 35 Low and 175~ High.

I observed my friend doing the recharge and noticed that he was vacuuming out for about 30 minutes as you stated. He also flushed the system of any moisture using nitrogen (I think). He then proceeded to add the refrigerant.

After replacing the condenser, I did NOT add any oil since I was not aware at the time. I later read in the service manual that I should add about 25ml of SP-10 oil after changing out the condenser. I will have to get that done soon.

 

Found the chart: high side at 103 blower max 1500 rpm 290 psi @30% rRH
low side 37 psi.
so the system seems a bit low
chemical flushing is only needed if compressor blew up sending metal shavings throughout the system; vacuuming will remove air and moisture.
This condition however should not stop the system from operating.

http://www.sanden.com/objects/SANDEN...OSIS_CHART.pdf

 

Thanks for the chart, I'll take a look at it more carefully once I get home from work. Do you think it's possible for the compressor to overheat from the ambient temperature or some sort of safety cut-off due to heat?

I say this only because the AC will stop working when it's pretty hot outside.

 

It could be combination of low amount of oil (that might be got flushed out) and heat.
(the receiver dryer is built into the condenser btw)

 

I will be adding some more compressor oil when my schedule frees up in the near future. I'll be reporting back then.

 

docotr J, I was able to fix my A/C issue! Unfortunately, I still haven't been able to add any oil to the compressor but I will be doing so soon hopefully.

Here is another thread I had going about my A/C issue.

https://www.fitfreak.net/forums/fit-...-cold-gd3.html

 

If pressure plate looks scored the compressor has some drag ; however it is hard to say what caused this.

 

Edit: Mis-Post

 

Seems awfully early to be drinking. LOL You posted this in a thread about A/C not working.

 

I swear I'm sober.
But I have no idea how this response got put in this thread.
I was in a thread where a poster was showing some "Hot Wheels" he had bought, including a "67 Mustang".

I don't think I even read this thread....until now.

Oh well......win some, lose some.