Pig rich code 33
Thread Starter
6th Gear
Joined: Mar 2018
Posts: 6
Likes: 0
From: Cincinnati Ohio
Pig rich code 33
First time posting here so take it easy on me but i've got a 1987 corvette automatic (stock) that is running extremely rich, Rough idle, hard to start, Smoke coming from exhaust, And a code 33, fuel in oil.
So far I've replaced my MAF, maf relays, ECU, O2 sensor, injectors (Bosch III), plugs, wires, changed oil.
I've sprayed for vacuum leaks and have found none. The car didn't smoke before replacing injectors but did have a fuel smell to it and rough idle to the point where it would want to stall out and die. I'm scratching my head on this one and just getting frustrated. I do all my own wrenching on the car and don't really want to have to drag it into a shop. Any help would be greatly appreciated.
So far I've replaced my MAF, maf relays, ECU, O2 sensor, injectors (Bosch III), plugs, wires, changed oil.
I've sprayed for vacuum leaks and have found none. The car didn't smoke before replacing injectors but did have a fuel smell to it and rough idle to the point where it would want to stall out and die. I'm scratching my head on this one and just getting frustrated. I do all my own wrenching on the car and don't really want to have to drag it into a shop. Any help would be greatly appreciated.
Instructor
Joined: Apr 2016
Posts: 163
Likes: 4
33 is MAF high per my code sheet. I’m not in front of my service manual right now but they have a trouble shoot step by step for each code.
Sounds like it thinks it is getting more air flow than it is. But all you replaced should have fixed this.
Wiring harness, connector to the MAF. also look k at throttle position sensor ??
Sounds like it thinks it is getting more air flow than it is. But all you replaced should have fixed this.
Wiring harness, connector to the MAF. also look k at throttle position sensor ??
Thread Starter
6th Gear
Joined: Mar 2018
Posts: 6
Likes: 0
From: Cincinnati Ohio
i have pulled the vacuum line to the pressure regulator and saw no fuel and didn't smell strong of gas (this whole engine bay smells of gas slightly no visible leaks though). I do not have a fuel pressure gauge to check if it's consistent but I will try to pick one up here soon.
Last edited by '87problems; Apr 22, 2018 at 09:25 PM.
Thread Starter
6th Gear
Joined: Mar 2018
Posts: 6
Likes: 0
From: Cincinnati Ohio
33 is MAF high per my code sheet. I’m not in front of my service manual right now but they have a trouble shoot step by step for each code.
Sounds like it thinks it is getting more air flow than it is. But all you replaced should have fixed this.
Wiring harness, connector to the MAF. also look k at throttle position sensor ??
Sounds like it thinks it is getting more air flow than it is. But all you replaced should have fixed this.
Wiring harness, connector to the MAF. also look k at throttle position sensor ??
Team Owner
Joined: Jul 2004
Posts: 28,462
Likes: 3,288
From: Hartford WI
First time posting here so take it easy on me but i've got a 1987 corvette automatic (stock) that is running extremely rich, Rough idle, hard to start, Smoke coming from exhaust, And a code 33, fuel in oil.
So far I've replaced my MAF, maf relays, ECU, O2 sensor, injectors (Bosch III), plugs, wires, changed oil.
I've sprayed for vacuum leaks and have found none. The car didn't smoke before replacing injectors but did have a fuel smell to it and rough idle to the point where it would want to stall out and die. I'm scratching my head on this one and just getting frustrated. I do all my own wrenching on the car and don't really want to have to drag it into a shop. Any help would be greatly appreciated.
So far I've replaced my MAF, maf relays, ECU, O2 sensor, injectors (Bosch III), plugs, wires, changed oil.
I've sprayed for vacuum leaks and have found none. The car didn't smoke before replacing injectors but did have a fuel smell to it and rough idle to the point where it would want to stall out and die. I'm scratching my head on this one and just getting frustrated. I do all my own wrenching on the car and don't really want to have to drag it into a shop. Any help would be greatly appreciated.
Team Owner
Joined: Jul 2004
Posts: 28,462
Likes: 3,288
From: Hartford WI
Does it have the problem in cold or hot? You said you replaced the injectors. Who did you get them from? What size?
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Thread Starter
6th Gear
Joined: Mar 2018
Posts: 6
Likes: 0
From: Cincinnati Ohio
injectors are Bosch III 22lb from FIC. Starts cold alright, starting warm is an issue; have to throttle it pretty good until it will idle on its own. I can see about borrowing a Bosch scanner from a friend. Not trying to "mechanic by throwing parts" everything I've bought thus far has made sense as a probable cause of issue. But your right about the scanner I need to just drop the money on one. If you have suggestions for a particular brand that works well with these cars I'd appreciate the insight.
Last edited by '87problems; Apr 22, 2018 at 10:33 PM.
Team Owner
Joined: Jul 2004
Posts: 28,462
Likes: 3,288
From: Hartford WI
I'd be wondering what the ECM is thinking the coolant temp is. Does it go into closed loop ever? I believe there may be 2 sensors. One for the gauge and one for the ECM so what does the engine THINK the temperature is? Are you sure you didn't disrupt anything or leave any sensor off?
Thread Starter
6th Gear
Joined: Mar 2018
Posts: 6
Likes: 0
From: Cincinnati Ohio
I'd be wondering what the ECM is thinking the coolant temp is. Does it go into closed loop ever? I believe there may be 2 sensors. One for the gauge and one for the ECM so what does the engine THINK the temperature is? Are you sure you didn't disrupt anything or leave any sensor off?
Team Owner
Joined: Jul 2004
Posts: 28,462
Likes: 3,288
From: Hartford WI
IF the temp is 70 and the scanner says it is 0, you know that something is wrong. To be sure, disconnect that sensor and see what the ECM says. Reconnect and see if it changes. If it does, hit it with the infrared thermometer and see what you have. The numbers should match within a few degrees. Another thing to see is what the ECM thinks the intake temp is.
Melting Slicks
Joined: Nov 2007
Posts: 2,830
Likes: 147
From: Gainesville FL
Check with Fuel Pressure Gauge - Injector Bleed down
If your FPR is OK then perhaps you have a stuck open injector. You would be able to tell if the fuel pressure bleeds down quickly after you turn off your engine.