Hello I'm new here and I have a major problem with my car. I hope you don't mind a long drawn out explanation but here it goes. So I have an 87 na I basically swapped over with a 93 13brew streetport engine and I also have a place here in Boise ID working on the wiring for it. We have swapped over the engine wiring harness from a 93 and connected it with the 87 dash and body harness. The upgrades I have are a 3 inch downpipe with magnaflow cat and muffler. I also have a prolite flywheel with 6 puck clutch. The engine is mild streetport with about 5000 miles. I have new rebuilt twin turbos on it. I also have a fmic with two hks blow off valves. All new silicone emissions hoses. New coil packs and plugs and wires. Cold air intake. The engine also had turbo II low compression rotors put in it. Now, to the problem, I have a major issue with cold starting. I have to turn the engine over about 20 times to get it to finally start. While turning it over it fumbles and then follows with a loud backfire about every 6th or 7th time I turn the ignition over. When it finally starts it seems like it is running great. The engine also cuts off at about 6000 rpm while driving. It hesitates and wont allow rpms to go past this. The shop that has the car says it is running to rich though. When its warmed up the car starts with no backfires. I hope I didn't bore anyone with my long drawn out issue but I really would appreciate any ideas. Pettit Racing said it could be a bad crank sensor or air temp or coolant sensor. I know I have also heard people having this issue alot if the the TPS is off spec. I have reposted this to build my thread count and get more opinions. In the next few days Im going to try to get a video of a first start up with this car so you can get a better idea of what is going on. I will also attach a video of the car running again to get some ideas. Here is a link for video of idle

 

i found out the thermal temp switch underneath the upper intake manifold is reading that its 40 below zero outside flushing large amounts of fuel into the engine. causing it to bog down and run like crap

 

How look that thing? I have the Same Problem...

 

yea my local maztech says they think there is a short in the wire to the sensor underneath the upper intake manifold. i let you know how they fix it

 

so what typically causes these kinds of problems then?

 

well the wiring harness i have was taken out of another fd. so who knows what they could have done to it. but it also could have been wired up wrong. Im paying a shop to wire up this car because im definetly not an electrician.