driveability problem

[87cracker]

Hi I purchased a 87 T-Type with a horrible bottom end knock but it still ran smooth I had a 1986 3.8 carb. engine laying around I purchased the correct drill and tap for the oil feed and return line to make it work for 86-87 models . It is a stock engine I have a modified 87 GN and this is just for a daily driver keeping it at 5-7 psi of max boost. I am having a bad divability problem with it . It runs horrible, backfires threw exhaust, and wont idle longer than 5-8 sec. I thought it was the cam sensor out of time I checked it 3 times and I even purposely put it out 180 deg to see if it was that. Its back fires threw intake and won't even start .

I put it all back to spec. I used my 87 as a ginnie pig and swapped: module, coil pack, cam sensor, crank sensor, injectors, ecm. 5 different chips, mass air flow . It doesn't even set a ck engine light. I did some research and the cams are different from non-turbo and turbo profiles, 40 psi fuel pressure. Is this enough to cause all these problems . I figured I wouldn't have the hp of a stock GN but I'm only wanted to use it as point a-b car nothing special, any body ever done this conversion before or even heard of this problem ?​

 

[hiboom]

First I'd hook up some sort of scan tool to verify that your iac and tps are with in specs. then I would check out your maf to make sure that it's working correct (tap on it lightly with a screw driver handle see it idle changes) then I would with car idling start wiggling the wires close to sensor connectors to see if there were any change in idle also look at crank sensor make sure its not rubbing or damaged I guess the ses light is coming on with key on no codes set?

 

[87cracker]

also forgot to mention I installed a new timing set, new front timing cover , new lower oil pump and gears.

 

[87cracker]

First I'd hook up some sort of scan tool to verify that your iac and tps are with in specs. then I would check out your maf to make sure that it's working correct (tap on it lightly with a screw driver handle see it idle changes) then I would with car idling start wiggling the wires close to sensor connectors to see if there were any change in idle also look at crank sensor make sure its not rubbing or damaged I guess the ses light is coming on with key on no codes set?

yes correct, ses light comes on when should , it starts up and as long as I keep my foot at 1/4 throttle or more it will stay running past the 5-8 sec and still no codes, also am running unbolted exhaust just have the factory down pipe installed to turbo, no cat

 

[hiboom]

I have in the past when one of my turbo blocks were in the machine shop (taking to long to get it back) put in a NA block to run using short block only, drilling for turbo return line and run for several month driving 120 miles a day with the car I turned the boost up a little more to give it a little more pep but the car drove and idled fine.It never hurts to double check .If it's backfiring it's probley a timing issue.If it was me the first thing I would do bring it up on TDC pull the number one plug and take the cam sensor cap off and make sure the window is in the correct posistion nad make sure the ring hasnt came lose.If all looks good there check fuel pressure with a gauge.I'll bet its something simple that will just take a little bit of time to trace down it frustrating when it won't set any codes.

 

[earlbrown]

First, you need to set the cam sensor dead nuts in the right place. It is also necessary to verify that you have full compression in each hole.

After that, verify fuel pressure, plug wires, TPS, IAC, etc....