I have a 1990 Ford F-150 302EFI. I went and got a sicker on my truck and it failed emissions. The HC grames per mile was over the limit of 3.20 it was at 3.88. They said the truck is dumping to much gas into the exhaust and said a sensor is gone, but what sensor is gone? It's it the O2, TPS, MAP, etc. Please let me know what you all think is going on with my truck, i don't have the money to have it put on a computer to find out what is going on with it.

Thanks Again Everyone.....

This is what was on the print out for the exhaust emissions test reseulys for transient test.
I live in Massachusetts

HC grams per mile (reading 3.88) limit 3.20
CO grames per mile (eading 31.42) limit 80.00
NOx grames per mile (reading 2.17) limit 5.00
CO2 grames per mile (reading 369.74) limit N/A

 

I have a 1990 F-150 302 as well. I would first check your o2 sensor, if you have a haynes manual it will tell you how to test it. Also most times the water temp sensor on the lower intake(below the throttle body) can cause emissions problems. If you cant afford to have the codes read like i did, I went to walmart and bought a code reader for $25 in the auto section and that will test you what sensor is bad. It easy to use and trust me, its worth the investment.

 

Thanks thomadm,
does the code reader connect to the ECU connecter on the drivers side wheel hub?

 

oh ya also there is a short in the back up lights and i can't find it i looked at the wires from the fire wall all the way back and nothing is grounding.

 

Yeah, the code reader connects to the ECU connector on the drivers side fender. As far as the reverse lights, do they stay on or they never come on? If they stay on then id say its the switch. If it doesnt come on it could be a bulb, connector, fuse, or that switch again. etc. Havent messed wth that on mine, maybe someone else can post and let us know? Hope this helps

 

You can read your codes for free, and it's just as easy as using the code reader.

http://www.broncodata.com/tech/codes.htm

 

I think either Autozone or Advanced Auto parts will also read the codes for free.

 

thomadm, I had to cut the back up wire on the inside of the firewall cause everytime I would put in in reverse it would blow the fuse. I put a test light on both of the wires - & + at one of the back up lights and put the other end of the to the body and it lighted up both time on the + and - wires so it's grounding some place. Do you think I could run a new wires back to the back up lights and put a swich in so i can turn the back up lights on manually, do you think they would pass that? Also my truck has trailer wire hook up and i disconnected that to see if the short was in that but it still blows the fuse. could the short be in the swich on the tranny?