Rpm Gauge Is Possesed!!!!!!!!!

[ICEMAN007]

Hey guys, it's been a while since I've posted. But I have a problem that I can't quite figure out and with minimal information, you guys might not be able to help. I just thought maybe someone has had this exact problem. Me and some of the MNSHO members did some maintenence work on my car and had the intake off, valve covers and the timing cover. After we slapped everything back together, I noticed my engine light comes on now and stays on. I ran the codes and there was an OPEN SPOUT code. Well since there was no physical or noticable signs of any problems, I just basically ignored the engine light. Now, two weeks later, my RPM gauge is going crazy, but not until the car has warmed up and the engine light comes on. When I am driving about 30 mph, you can't really notice anything, but when you get into the 40-45mph range, and you let off the gas after maintaining a steady speed, the RPM guage's needle will drop all the way down to zero and then will sky rocket up to about 5 or 6k and keep doing that sparatically until I step on the gas pedal. The engine is not running those type of RPM's, it's just the gauge going crazy. But there is hesitation when I press back down on the gas pedal when the RPM gauge is acting up. The car will **** just for a second until the rpm gauge maintains the proper revolution point. I'm thinking that there has to be a short somewhere or could a sensor be bad or getting bad? Does anyone have any ideas here????? All your help would be greatly appreciated!!! Thanks so much, -C

 

[SHOtimer]

Sounds like you have a grounding problem on your intake. I would check all of the grounds, like the crossover tube, and especially the ground strap, from the intake to the firewall.

Doug

 

[somedude_001]

Sounds like you have a grounding problem on your intake. I would check all of the grounds, like the crossover tube, and especially the ground strap, from the intake to the firewall.

Doug

+1

also if you have a code for a disconnected snout connector why didn't you plug it back in?

 

[whiteman_01]

Ok, dumb question time. Where is the spout connector??

 

[turbo79]

FYI, I believe that the tach is "driven" by the camshaft position sensor (CMP). Maybe the wire connection(s) to it were damaged when you were working with the valve covers off?

The CMP is on the front side (passenger side) of the engine, on the rear bank of cylinders up near the valve/cam cover.

 

[SHOtimer]

The spout connector is hanging over by the CID sensor.

The tach is driven in a combination between the CID, CPS, sensors and the DIS module.

Doug

 

[ICEMAN007]

Ok guys, so I monitored the SHO very closely this morning on the way to work, which is 35 miles of highway. So about 5 minutes onto the highway the CEL came on, as usual but it took a good 15 minutes before the RPM gauge started to act up and go bezerk. Well tonight, on my way home from my daughters basketball tryouts, I noticed it acting worse and much more drastic with the RPM gauge than normal. As I turned off of the exit ramp, every gear I shifted through gave quite a bit of hesitation and jerkiness while pressing down on the gas pedal. The car then died on me. So I pulled it over, started it back up and tried to get her home as I was only about 8 blocks away. Then, once again it killed for a split secong but then turned right back on and I continued to drive home and parked her in the garage. Guys, I have no idea what is happening but it seems to be getting worse. My car has never died on me before so I am taking this very seriously. What could we have done wrong by taking off the intake, valve covers and the timing cover to create this madness? All your suggestions are greatly appreciated and please keep them coming. Thanks so much, -C

 

[whiteman_01]

Time for a cam or crank sensor. I would start with the cam sensor though. Its the cheaper part, and easier to replace.

 

[SHOtimer]

All your suggestions are greatly appreciated and please keep them coming. Thanks so much, -C

Have you tried looking at the grounds and the intake strap?

Doug

 

[Devin]

++. I've found that grounds in this car are almost as important as gasoline and oil.

 

[ICEMAN007]

Hey boys, just a follow up here to the original problem. So the possible causes were a bad ground, cam sensor or the crank sensor. So I went out and picked up the cam sensor, and since it was the cheapest of the two and the easiest to install, I decided to try that first. Well, the install from start to finish took only about 20 minutes and yup, it's fixed!!!! :hdance:I think. Lol. I drove the car for about a half hour and didn't have any signs of demons or ghosts in my instrument cluster. The true test will be tomorrow as my drive in to work takes me about an hour to get there.

The crank sensor was actually an OEM part and my car has 160k on her. I guess it was a little overdue! I'm sure the crank sensor will be next to go and I should probably just replace that sometime soon to avoid any further headaches. Reason being why we are supposed to do the 60k every 60k! Otherwise these cars can be a real headache!!! :fight:Thanks for all the responses and help guys. Take care, -C

 

[LiLGhettoSmurf]

Sounds like a problem I had on and off for like 2 months, when I had the water pump replaced and I had the Cam and Crank sensors replaced and I've never had the problem since.

 

[turbo79]

Hey boys, just a follow up here to the original problem. So the possible causes were a bad ground, cam sensor or the crank sensor. So I went out and picked up the cam sensor, and since it was the cheapest of the two and the easiest to install, I decided to try that first. Well, the install from start to finish took only about 20 minutes and yup, it's fixed!!!! :hdance:I think. Lol. I drove the car for about a half hour and didn't have any signs of demons or ghosts in my instrument cluster. The true test will be tomorrow as my drive in to work takes me about an hour to get there.

The crank sensor was actually an OEM part and my car has 160k on her. I guess it was a little overdue! I'm sure the crank sensor will be next to go and I should probably just replace that sometime soon to avoid any further headaches. Reason being why we are supposed to do the 60k every 60k! Otherwise these cars can be a real headache!!! :fight:Thanks for all the responses and help guys. Take care, -C

Glad you're better now. I got the "advice" about the tach being driven from the CPS off of SHOTimes. I replaced mine (139,000+ miles, got the car recently) just as insurance.

I'd replace the crank pos sensor (CKP) ASAP, because when that goes you'll coast to a stop, dead in the water.

Best of luck!