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So I posted about 2 or 3 weeks ago about my cars rpm jumping and got a lot of responses and thought I had figured it out. I replaced the HEI mod and made sure it was securely grounded and my car ran fine...then it rained and it started jumping again and stalling. So I checked the O2 sensor thinking it may have gotten wet...when I did one of the prongs on the plug broke off because of how brittle it was. I replaced the prong and it started back up and as of now seems ok but I decided to run the CEL codes since i hadnt before just assuming it was the EGR code, but I got a lot more than I bargained for, and need a little help deciphering them it was as follows:

2 short
3 short
1 long
6 short
1 long
1 long
8 short
6 long
7 short

I figured it as 2 (crankshaft position sensor), 3 (camshaft position sensor) 16 (egr system), 28 (egr vacuum solenoid) but the 6 and 7 at the end throw me off. Any help would be appreciated, plus Im not too sure what the codes mean and which ones would cause such horrible rpm jumps? :/ sorry...I feel stoopid

I think you're right about the codes. 6 and 7 is probably repetition of earlier codes.

67- Cooling fan relay or circuit

Probably is the TPS out of range. To get the TPS back in range follow the FAQ to adjust the TPS. Then set the idle.
When you modify the TPS, you change the base idle, which changes the base timing.

When you adjust the base idle (with the idle air screw) and the base timing, you will change the TPS.

So you have to adjust the TPS, then adjust idle/timing. Then readjust the TPS, then idle/timing. Continue to perform this function until all three variables are set.

[quote="SuperK"]67- Cooling fan relay or circuit

Probably is the TPS out of range. To get the TPS back in range follow the FAQ to adjust the TPS. Then set the idle.
When you modify the TPS, you change the base idle, which changes the base timing.

When you adjust the base idle (with the idle air screw) and the base timing, you will change the TPS.

So you have to adjust the TPS, then adjust idle/timing. Then readjust the TPS, then idle/timing. Continue to perform this function until all three variables are set.[/quote]

Thank you! its definitely the code for the fan because I unplugged it and ran my own switch. I'll have to try adjusting everything when I get home...if it works will the codes stop going off for the camshasft and crankshaft sensors? And if it is off now could that cause my symptoms of uneven rpms while driving/stalling?

thanks again I'll keep you updated

Probably won't fix the cam and crank sensors. But it is a free troubleshooting step that should clear the hunting. The crank sensor probably will need to be replaced. The cam sensor is built in to the distributor.
Take care of the free parts then work your way to clear the sensors that cost money to replace is my suggestion

Hopefully you've got this sorted, so my input unnecessary. Just in case: Once you set the TPS you don't need to return. All you are setting is the closed throttle position signal to the ECU. It is a setting that does not change regardless of the position of the idle air screw or timing. Ideally you warm the engine to prepare and idle by that time is near spec of 650 - 700 RPM. If not adjust the idle speed with the idle air screw. Adjust timing next. You might have to repeat timing and idle adjustments, but TPS is not going to change.

I believe if your cam sensor is bad the car will crank for like 1/2 a minute then finally start. This is the ECU looking for the signal then basically saying fu*k it,,,kinda Don't forget to jump Ten and Gnd before setting the idle right. Set it to 650 then when you remove the jumper the rpm will go to 700. Same for the timing, jump Ten and Gnd.