2g head on a 1g block.....help!
Revan
03-09-2005, 02:17 PM
I've completed building and installing the engine. It's a 1g block with a 2g head. I've done all the mods required but it will not kick over. It starts and is trying but for some reason its not going. I've troubleshoot and found that the fuel pump isn't making any sound. I'm also using the 1g CAS too. help me out please. Thanks.
97_3clipse
03-09-2005, 04:13 PM
why did you do this? 2g head on a 1g block? why?
Revan
03-09-2005, 07:47 PM
Well, I wanted to have the 6 bolt without having to change the wiring. BTW, just to make sure. The cas for the 2g can be right under the cam gear?!
kjewer1
03-09-2005, 09:05 PM
I would check into the cas wiring first. Are you using the 1g cas to generate both signals, or just the crank signal? Uninstall the 1g cas, and turn it by hand with the key on the on position. You should hear the pump kick on and the plugs/injectors clicking. If not, the cas is bad, or the wiring is bad.
Edit> this may be a stupid question, but you never know. You did change the plug wire order right? It should be backwards after installing a 1g CAS. Swap the 1-4 and 2-3 pairs with each other. 2-3 on the 1-4 coil, etc.
Edit> The cas for the 2g can be right under the cam gear?!
It is on 95-96 heads. On 97 up its in the same location as the 1g, but its still only provides the cam signal and a crank sensor is used, unlike 1g where it provides both from the cam sensor.
Edit> this may be a stupid question, but you never know. You did change the plug wire order right? It should be backwards after installing a 1g CAS. Swap the 1-4 and 2-3 pairs with each other. 2-3 on the 1-4 coil, etc.
Edit> The cas for the 2g can be right under the cam gear?!
It is on 95-96 heads. On 97 up its in the same location as the 1g, but its still only provides the cam signal and a crank sensor is used, unlike 1g where it provides both from the cam sensor.
Revan
03-09-2005, 09:44 PM
I'll check on the wiring when it I get a chance. Should I just go with the 1g cas or the stock cas?
TsiTalon9587
03-09-2005, 11:05 PM
Just as reference, do you have any way to prevent the cel you *will* get from the 1g cas?
kjewer1
03-09-2005, 11:50 PM
You have no choice but to use a 1g cas to supply the crank signal. If you use the 1g CAS to also provide the cam signal, 99% of the time you get that CEL/Limpmode. If you use the 2g cam sensor to provide the cam signal, I dont know what would happen. It might work, it might still give the CEL.
Revan
03-10-2005, 09:42 PM
I switched the plugs and the engine came to life. I had too tap power straight to the fuel pump motor. The car started and turned over but didn't last long. I think the fuel pump relay may be bad. Can anyone tell me where it is and do you have any idea what else it might be?
kjewer1
03-11-2005, 08:31 AM
Well, that sounds like a step in the right direction anyway.
What exactly is your CAS setup, I need this to be clear or I cant offer much help. For example, I've seen an intermitently bad 1g CAS let the car run for a bit then shut off. Start it up, runs for a bit, and shuts off. I know, because this left me stranded in a parking lot somewhere far from home for an hour or so until I finally called a truck in. How I diagnosed this as a bad cas in the dark at 2 am is beyond me though. I used to know what I was doing it seems... If you are using a full 1g CAS to generate both signals, again, uninstall it, and turn it by hand with the key in the on position. If you dont hear the pump running and the injectors, its bad. If the injectors are clicking and the pump is not running, its in the pump wiring.
Edit> If you had the pump wired right to the battery and it stalled, its not the fuel pump relay or anything like that in that case, because you bypassed it. Not sure what you meant there. I think more info is needed :)
What exactly is your CAS setup, I need this to be clear or I cant offer much help. For example, I've seen an intermitently bad 1g CAS let the car run for a bit then shut off. Start it up, runs for a bit, and shuts off. I know, because this left me stranded in a parking lot somewhere far from home for an hour or so until I finally called a truck in. How I diagnosed this as a bad cas in the dark at 2 am is beyond me though. I used to know what I was doing it seems... If you are using a full 1g CAS to generate both signals, again, uninstall it, and turn it by hand with the key in the on position. If you dont hear the pump running and the injectors, its bad. If the injectors are clicking and the pump is not running, its in the pump wiring.
Edit> If you had the pump wired right to the battery and it stalled, its not the fuel pump relay or anything like that in that case, because you bypassed it. Not sure what you meant there. I think more info is needed :)
Revan
03-11-2005, 09:59 AM
I disconnected the 1g cas and used the stock cas. the cas sensor and the original connector are at opposite ends of the engine so I cut, stripped, and connected an extension. I matched the wires the best I could. red to red, black to black, and I assume that the blue goes to the blue with red stripe. tell me if i missed anything.
I noticed a connector that I have no idea where it goes. it has 4 wires. black, yellow, white, and red. when I installed the 1g cas the wires matched but 2 wires where swithed. I check chiltons and it has the connector as some kind of heat sensor. What do you think?
I noticed a connector that I have no idea where it goes. it has 4 wires. black, yellow, white, and red. when I installed the 1g cas the wires matched but 2 wires where swithed. I check chiltons and it has the connector as some kind of heat sensor. What do you think?
Revan
03-11-2005, 10:07 PM
What would cut off power to the fuel pump?
kjewer1
03-12-2005, 03:24 AM
I'm assuming this is a 95-96 CAS, based on your question about the cam gear above. Putting your car in your sig would be helpful, its hard to believe some poeple havent done this yet. ;)
This (http://www.roadraceengineering.com/1gcasin2g95-96M2.htm) is the diagram showing you how to wire things up. If you are still using the stock crank sensor, I dont see why you can't just do the cam sensor portion of this wiring.
Blue wire goes to 1g CAS pin 1
Red power wire goes to 1g CAS pin 3
Black ground goes to 1g CAS pin 4.
1g CAS pin 2 is for the signal (blue) wire from the crank sensor, if you are using the 1g CAS for both, or unused if you are only using it for the cam sensor. You know, I seem to remember already having asked that question. If poeple dont start answer the questions I ask, I'm going to flat out refuse to help. I dont ask these things for my health, or to make my car faster, but to ensure that I am giving you the right advice, or to decide if I just don't have the answer, etc.
Wiring color to color is not advised, colors change over the years and even sometimes within the same year. Hopefully this is how you hooked things up, or if not, hope that nothing was permanently damaged. Good luck.
This (http://www.roadraceengineering.com/1gcasin2g95-96M2.htm) is the diagram showing you how to wire things up. If you are still using the stock crank sensor, I dont see why you can't just do the cam sensor portion of this wiring.
Blue wire goes to 1g CAS pin 1
Red power wire goes to 1g CAS pin 3
Black ground goes to 1g CAS pin 4.
1g CAS pin 2 is for the signal (blue) wire from the crank sensor, if you are using the 1g CAS for both, or unused if you are only using it for the cam sensor. You know, I seem to remember already having asked that question. If poeple dont start answer the questions I ask, I'm going to flat out refuse to help. I dont ask these things for my health, or to make my car faster, but to ensure that I am giving you the right advice, or to decide if I just don't have the answer, etc.
Wiring color to color is not advised, colors change over the years and even sometimes within the same year. Hopefully this is how you hooked things up, or if not, hope that nothing was permanently damaged. Good luck.
Revan
03-12-2005, 10:10 AM
I've decided not to use the 1g cas. I stuck with the stock cas. There are 3 wires. I assumed the colors matched. If i'm wrong please correct me. I also noticed that the o2 sensor is not connected the harness has a square connector and the o2 connector has a round one. Is that right? Thanks.
kjewer1
03-12-2005, 10:17 PM
There are two sensors on the 2Gs. The crank sensor is on the block The other sensor, the cam sensor, is under the intake gear on 95-96s and can NOT be used on a 1g head without some machine work to provide a place to mount it. The 97-99s use a cas in the same location as the 1g cas, but will only work with 97-99 intake cam, without having to modify the cam anyway. The 1g CAS provides both the crank and the cam signals from one unit.
In your case, a block only swap, you cna use the stock cas. I was thinking you were doing a head only swap BTW. So there should be no wiring changes to the cam sensor. The problem is the 1g oil pump cover will not have provisions for the crank sensor, since no 1g used one (again, part of the cas). So you will need to use a 1g cas to provide that crank signal. Without, youre up shits creek.
Now, back to what I was getting at before. You can use the 1g cas to provide both signals, and have a 99% chance you will get the random misfire DTC/limpmode, and have to go with DSMlink, or the baro wire mod and AFC. If you use the 1g cas for the crank signal only, and use hte stock 2g CAS, I'm not sure if it will be any less likely to get that RM DTC. Either way, you have to use the 1g CAS for the crank signal, wired in using the instructions posted on the RRE page linked to above.
I dont even remember what the original question was now, but if hte car wont run, having no crank position feedback may be the cause ;)
2Gs use a square connector on the O2 sensor, 1Gs use a round cnnector. Are you trying to use a 1g O2 sensor on a 2g car?
In your case, a block only swap, you cna use the stock cas. I was thinking you were doing a head only swap BTW. So there should be no wiring changes to the cam sensor. The problem is the 1g oil pump cover will not have provisions for the crank sensor, since no 1g used one (again, part of the cas). So you will need to use a 1g cas to provide that crank signal. Without, youre up shits creek.
Now, back to what I was getting at before. You can use the 1g cas to provide both signals, and have a 99% chance you will get the random misfire DTC/limpmode, and have to go with DSMlink, or the baro wire mod and AFC. If you use the 1g cas for the crank signal only, and use hte stock 2g CAS, I'm not sure if it will be any less likely to get that RM DTC. Either way, you have to use the 1g CAS for the crank signal, wired in using the instructions posted on the RRE page linked to above.
I dont even remember what the original question was now, but if hte car wont run, having no crank position feedback may be the cause ;)
2Gs use a square connector on the O2 sensor, 1Gs use a round cnnector. Are you trying to use a 1g O2 sensor on a 2g car?
Revan
03-13-2005, 02:34 PM
Ok. I've checked the cas, crank sensors and I replaced the plug wires. I haven't connected the O2 sensor because the O2 connector was missing so it is exposed. The engine is running strong for a few seconds but then starts to deccelerate into a stall. What do you think?
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