# Psyco-Clone **URL:** https://forums.speedlife.net/t/psyco-clone/185561 **Category:** Builds **Created:** [October 12, 2006, 5:43pm UTC](https://forums.speedlife.net/t/psyco-clone/185561 "2006-10-12T17:43:59Z") **Posts on this page:** 1 **Showing post:** 151
### Author: ![SixSpeed454SS](https://avatars.discourse-cdn.com/v4/letter/s/e19adc/32.png) [@SixSpeed454SS](https://forums.speedlife.net/u/SixSpeed454SS) #### Post date: [April 6, 2007, 8:42pm UTC](https://forums.speedlife.net/t/psyco-clone/185561/151 "2007-04-06T20:42:50Z")
> [@WTF internet?](https://forums.speedlife.net/t/wtf-internet/28479/316): > > there are 2 marks on the balancer, i marked the wrong one. :kekegay: > > but NOW, the timing is good, the ECM is good, i just found my fuel pressure was at 50psi, i dropped it to 42psi. Truck starts on the first click, is firing smoothly, no knock, injectors are pretty loud, but good. > > only problem is i must have a bad sensor somewhere, 99% sure its a bad O2. Cause the truck will idle finefor 10 seconds when i first start it up, but then it idles rough (i believe after the ECM starts taking info from the sensors). > > I’ve replaced everything else, so this must be it. when the truck is first started, it takes more than 10 seconds to have the ECM reading the O2. The O2 is ignored until the water temp gets to a certain level. The engine runs in “open loop” during this time & the O2 is inactive. Once the ECM goes to “closed loop”, then it starts to read the O2. I would check your MAP, or even check the voltage to a few of the sensors. Did you make sure all the grounds were connected & the paint cleaned off where they connect? On these EFI systems, ground is very important. Check the voltage on the TPS & MAP. You have 3 wires on each. One is ground, one is +5V dc, & the other is the output from the sensor to the ECM. This should read as low as .5 volt up to 5 volts throughout the movement of the sensor, with no dead spots in between. If your ground is poor, then you will not be getting a full 5 volts to the sensor. Also, if the temp sensor is not working properly, the ECM may think the water temp is higher than it actually is, so the ECM may go into closed loop sooner than it should. This can cause erratic idle quality. --- _[View the full topic](https://forums.speedlife.net/t/psyco-clone/185561)._