Ford Mustang Forum banner

89 mustang LX

5K views 66 replies 6 participants last post by  88LXsleeper 
#1 ·
So here goes. My mustang has a 302. Only things that have been done to it are; msd cap and wires, msd blaster 2 coil, accel dist and rotar, Cold air intake, long tube headers, off road h pipe to a axle back 30 series flow masters.

So with that being said, i have a few issues. 1. OBD1 scanner says bank one and two are rich. 2. On a hot day i have to have WOT it to get it to start, it will rev to 2900-3000 grand then slowly work back to what i have it set at, about 900rpm. 3. Check engine light is intermittent. I ran a KOEO no codes system passed, KOER i get codes 33,92,42 and 21 in that order.

33. Canister or EGR valve not operating properly. (OBD1 Scanner indicated no egr flow detected)

92. Fuel mixture rich, fuel pressure high.(OBD1 Scanner indicated bank 2 rich)

42. Fuel mixture rich. (OBD1 Scanner indicated bank 1 rich)

21. Coolant temperature sensor out of specified range.(I run the car w/o a thermostat)

What is going on. Also i will list off parts i have replaced as you ask about them. I will say this. The car has been having thisnissue for a long time. Not even local mechanics can figure this out.... please help. My fuel consumption is outrageous for a stock mustang. Im talking in the low double digits if not single digits. And no i do not have a fuel leak from the car.
 
See less See more
#2 ·
To start running without a thermostat can cause plenty of issues. If the car never reaches temp the computer will never come out of open loop mode. The car will just continue to run rich in an attempt to get it to warm up. Put a thermostat in it. Check your plugs to confirm that the car is running rich. Check for vacuum leaks. Are you also positive the injectors haven't been switched out at some point in the cars life?


What about continuous memory. If the car has flashed the CEl there will be a code in the CM.
 
#3 ·
Read some of your older posts. Did you ever put a vacuum gauge to it?
 
#4 ·
Yes, vacuum is good, no leaks. I will install a thermostat this Friday or Wednesday. No the injectors are OEM. They have not been replaced. The issue started after i got the car. Also to shed just a little bit more light the "flooding" only happens when its 80° or warmer. It runs rich all the time though. By flooding i mean at all speed i can get a throttle response delay. After i put it in neutral and quickly rev it to 5g and back down a few times it clears up. Plugs and wire replaced earlier this month. MAF, IAC, TPS, O2's, rotor, cap, BAP, temp sensor... well hell all sensors except for the knock sensor have been replaced, at least 2 times over the last 4 years. Wires and plugs are as needed.
 
#5 ·
Which "temp sensor" have you replaced. IAT? ECT? Those two could be mistaken for each other pretty easy. Ill try to find the thread or info on how to individually test the ECT sensor. I know you replaced them all, but are the other sensors within spec? TPS voltage within .5-1.1vdc? MAF @ correct voltage?

PS. your car doesn't have a knock sensor.
 
#14 ·
Judging by your computer it doesn't recognize that the smog pump is gone. It doesn't care and doesn't need to be tuned. Both your MAF and TPS appear to be within spec at idle.
 
#18 ·
Quick question how does it run once you're up and moving? Any bucking/chugging, stalling, etc?
If you replaced the egr valve you'd probably remember. It kinda looks like a bell and if you replaced it it would be new a shiny, either gold or silver. You can take your old one off and clean it to see if it fixes your problem. But they're not that much and it'd be easier just to replace it. But before I did that I'd look at the vac lines that go to the egr solenoid. They look like coffee stirs (ones green) and they're under the passenger side fender well if I remember right. Here's a decent write up that some guy did on egr stuff. http://www.stangnet.com/mustang-forums/threads/egr-solenoid.691188/
I think you're coolant codes are due to not having a t-stat. The hard start stuff could possibly be a bad pip which is like a crank position sensor for your model and it is pressed on to the distributor. It'd be cheaper to buy a new distributor unless you have a press.

Sent from my iPhone using Tapatalk
 
#21 ·
I just came back from a test drive. CEL came on then did not come back on after i put gas in it. It might be the EGR code. I wont know till tomorrow when i can get a scan tool on it. Also it did not run rough. I know its still running rich. I can smell a little bit of gas in the exhaust but not nearly as much as i have recently. Could the computer be running in a "egr tune" if so what is the tune is it supposed to lean it out or run it rich?

Sent from my SM-G920V using Tapatalk
 
#22 ·
Last but not least this is all of these issues are after a warm start up. I probably should have mentioned this in the first post. On a cold start up its 10 times better. Still rich but its supposed to be in the closed loop, cold start up. As i woild assume

Sent from my SM-G920V using Tapatalk
 
#27 ·
Cold start up is Open loop. Car doesn't care about the O2 sensor (disregarding O2 readings is essentially what open loop is) readings until it reaches around 160 degrees. Now considering that you put a tstat in and its still throwing the ECT temp code I suspect that is faulty. The Ect is one of the main players when it comes to the computer deciding how much fuel to put in the car.

Here's what I think is the issue. Considering you said the car runs fine when it first starts and runs for a bit I'm really starting to think the ECT is throwing everything off. Its not showing any temp so the car thinks its cold. The computer essentially does what its supposed to but as the car gets hot all that extra fuel is not needed, causing the issues.



As others have said make sure you put your timing up to 10BTDC, the stock setting.
 
#28 ·
#31 ·
For the green vac line i made a temp fix with electical tape. Before i couldnt feel air flow from the white vac line to the egr. Now i feel a pulsating positive air pressure from it. Shouldnt it be negative pressure. (a vacuum instead)

Sent from my SM-G920V using Tapatalk
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top