Here's a problem I'm having that NOBODY can figure out.. Lets see what you guys think:

So my issue started a month ago when I got into it in second, and saw knock so I let off. the car drove normal for a moment, then hesitated and died basically. I had it towed to a shop where they saw the check engine light was on for a bad crank sensor (got destroyed by the reluctor wheel when the previous owner had the T belt changed and they bent it). So they changed the crank sensor, both cam sensors, and tossed in a new timing belt.

I drove the car home, drove it for a half hour afterwords with no issue, let the car sit for an hour then went to go to work with it and I had the issue again where it hesitated and died on me. After this happened again, I had my tuner put a new tune on it, but we noticed we couldn't log for some reason, it shows that the computer is connected, but it doesn't pull up any info (Rpms, ect), nothing.. So we load the new tune on there anyways, and drive around for quite a while without any issue, then eventually it bucked and died again. I get it back to the shop as the cam sensor light came back on (intake cam sensor), so they changed that out again, but the check engine code still was there even after erasing it..

So we today relocated the battery to the trunk as I had a half size with only 170cca that we figured may be the issue, (because it was needing to be jumped to get started and would need jumped if it just sat over night). Now, even with an 800cca battery in the trunk I took it out, and drove it maybe 60ft and the car hesitated and died.. So we can NOT find the issue no matter what. Here are the mods and what has been changed trying to fix this BS issue..

-Evo IX
-73,xxx miles
-Stock turbo
-stock injectors
-aeromotive 450 fuel pump
-map 02 dump 3 inch downpipe, catless, 3 inch greddy catback
-speed density intake and sd tune with 4 bar map sensor (was replaced in july and retuned since installing twice now)
-short route intercooler piping
-viper alarm
-aem wideband

stuff we've tried to fix this issue*
changed starter
new tune
full size battery
new cam, and crank sensors
checked wires on crank and cam sensors for fault
checked resistance on starter wire
bypassed starter wire on the alarm

I'm at a loss, and since we can't log I don't know what to do to fix this issue.. any ideas at all would be truly appreciated, I just want my car back.

 

Are you sure all the connectors of all the sensors including the throttle position sensor are intact to their locations and on the ECU pins? also, what did you guys exactly do with the "bypassed starter wire on the alarm"?..... can you revert it back to stock form and note any difference?

reason why I ask about the connections, is it is possible that some may lose contact or sending the signal to the ECU due to vibrations or lack of installation. As a result, the ECU will shut down thinking its a problem (stock ECU).

 

have you checked and tightened all your chassis grounds?

 

Yeah I would think they should all be fine as there hasn't been any change to them, are there any in particular you would recommend I check aside from the throttle position sensor? The shop that has been working on my car was basically trying to make sure the starter wire that's hooked into the alarm wasn't the issue, so I believe he just bypassed that section of the alarm which brought that part of the alarm back to stock, with no change he just undid what he did with the alarm wiring. I wasn't there so I can't know for sure.

 

I haven't, could a bad ground cause this issue? If so it's worth looking into

 

I would suggest checking all the sensors (TPS, IAC, knock, cam, crank, grounds...etc).

 

bad grounds can cause all kinds of electrical havoc

 

Had the tps tested, and my buddy who is looking at the car said that he was seeing some weird readings from it, so we have a new one that will be here tomorrow, hopefully that helps this issue. Thank you for the suggestion!

 

yw, hopefully it resolves your issue!
check the connection of it to the ECU. That pin may be lose....especially if the car has had an aftermarket ECU in the past where they tried to re-pin the TPS onto the new unit.

 

check the map sensor, easiest way to know if thats the problem is when the car is on just wiggle the map sensor and see if the car shuts off.