Car not running right? Here's some common debugging tips!
1. Engine running warmed up, unplug the blue coolant temp switch, does anything change? No = bad coolant temp.
Alt: 1000 ohms resistance after normal operating temps
2. Air Temp (on intercooler tube) 500 ohms on outer two pins, you have to drill out the cap to get the adjustment.
3. O2 sensor, of course, check the wires/harness for any damage. If you haven't replaced this lately, might be time to get the universal and just crimp the wires on. $60 or less.
4. The TB -> ecu hose must be plugged in the right place. its closed to the passenger side. Unplug the ecu hose from the ECU , if the car still runs like crap, then its the ecu hose. Don't even attempt to drive the car with the ecu hose off.
5. Check your battery voltage, If the battery voltage goes low, the ECU dumps 25% more fuel than normal.
6. The ground wires, to the head, and everywhere else. Bad grounds are a common issue with this car, especially the one to the head.
7. Distributor cap/rotor, remove, inspect and clean dirt. Sandpaper any "growth/corrosion" on the metal contact points.
8. Wires,plugs, you should remove the plugs and inspect for damage, or fouling from being rich.
9. If o2 sensor goes bad, it will kill the cat real quick. Remove the cat by lowering exhaust, look inside, if its crumbly, turned sideways, or black, its probably dead.
10. Check vacuum through boost gauge (10-15psi of vacuum) or MFA (84-104) at idle. Anything else, you might have a big vacuum leak.
11. ISV - if you haven't rerouted it, you may have a leaking ISV.
12. Idle screw on throttle body. Make sure its not gone, or about to fall out. Usually results in "hunting" or high rpm idle.
13. Have you changed the fuel filter lately? Its by the passenger rear wheel. Easy to change, watch out for gas spraying you in the face!
14. Timing. If you don't own a timing light, you can mark the distributor cap and base with some paint/white-out. Unbolt the ~13mm bolt that holds the distributor down.
Turning the distributor cap right, will retard timing, Turning left will advance. Advance = more power, quicker off the line, more likely to ping/knock with poor gas. Retard is when you feel
pinging or detonation. I'd suggest, on the hottest day possible, advancing a little, driving, and advancing more until you feel knock/detonation or pinging when you first get on the gas. Then back off some.
Stock timing is 6-8 degrees, with good 93+octane gas , you should be able to go higher. With poor 91 octane, you are going to have to back off timing a bit with most chips.
Do you know how to test your boost levels?
1. Start Motor
2. Move the MFA selector to "2"
3. Press and hold the MFA end button (keep holding)
4. Stop motor
5. Start Motor
6. Release the MFA end button.
7. Press the MFA End button one time.
You should now see 84-104 readings fluctuating with idle. Anything higher than 104 is not right (vacuum leak). Much less than 84 is probably too much timing advance.
Go run your car!!! 3rd and 4th gear to REDLINE. Carefully note the highest #'s you've got.
A pullied charger should not make less than 11.6psi, and even so, thats weak. A Stock charger should make ~~11psi in perfect shape!
USA EURO Hg(#'s of boost/vacuum) Comments
15 200 -23.7
55 400 -17.8
90 600 -11.9
127 800 -5.9
148 1000 0 (Atmosphere- ala no boost, charger is bypassed)
172 1200 2.9 psi (Your charger is dead or big boost leak)
192 1400 5.8 psi (Your charger is about dead or big boost leak)
211 1600 8.7 psi (Your charger needs new apex strips or big boost leak)
228 1800 11.6 psi (Great for stock pulley, Probably needs new apex strips if 68mm pulley)
242 2000 14.5 psi (Great for 68mm pulley on stock charger)
255 2200 17.4 psi (Great for 68mm pulley on heavily ported charger, hold on to your ass fast!!)
255 and up folks need to be careful with fueling, as the programming maps end at about 242 on the ecu :) Dynotuning, and air/fuel/egt gauge, and custom chip recommended