I have a 1992 400 and it's the check engine light isn't on I bought it for 3k has 150k miles on it drove it for a month daily straight 40 miles a day 20 to work 20 home calm steady 70mph on 45 out here in houston TX car was fine no issues then out of no where one morning I started the car up and it sounded different and it had like no power it when in drive and idle rolling it moved fine and when I pushed on the gas I got some acceleration but after a certain point I have to push the gas all the way down to even get the car to go like 40mph and also the ac decided to stop working that morning as well give me a email if you can help me sk8deathwish@yahoo.com

 

The two issues might just be coincidence without correlation.When it come to starting at the least expensive part first, I would replace your fuel filter. sounds like it is struggling for gas..if its running now, I would also consider putting some seam foam in the gas tank and see if it flushes the clog out..

Not a mechanic, just where I would start

 

Another thing to consider when a 400 starts acting up is the fuel pump relay. There are several theeads on here about where to find it and how to make a jumper for it. It's pretty much free so is another good place to start.

 

Relay sensor huh, I may need to look into that I'm going to test the pump today and see if I can hear it turn on when j turn the key I just wouldn't think it was the filter or fuel pump at only 150k those usually last longer I thought

 

Check the fuel pump module which is behind the left rear interior panel. You will have to remove your back seat to get to it. As for the ac part, check if it has Freon in the system. Start with the easiest first then work from there.

 

The ac doesn't even turn on at all..

 

Like the compressor or the ac control panel does not turn on?

 

The control panel inside it doesn't turn on and nothing displays anymore

 

I should check if the compressor turns on but rn I'm screwed getting it to start its sat for a week and I've not been able to jump the battery

 

Well start by checking the fuses. Was the display visible before? or was it getting black like it was bleeding or something. But first make sure your battery is good.