1G 90 ecu swapped into 91 runs funny now

[gabe600r]

I have to crank my car a lot and off and on when it sits awhile it starts to spudder then will start but wont idle without me giving it gas.

I had this same problem with my other car before I scrapped it. I used my head intake and fuel injectors from that one on this car and am having the same problem. I did change the coolant temp sensor thinking that was it but wasnt.

I swapped my 91 ecu with a 90, swapped pins 6 and 14 green wire and green with white stripe, now car runs seems real rich and has a miss at low speeds but runs fine under boost. what could this be?

 

[92AWDHX40]

Check the coolant temp sensor find some way to check codes.

 

[BlackTsi1992]

Could be the fuel pump also. If its harder to start after it sits a while and you have to cycle the key, the fuel may be draining back into the tank thru the feed line loosing your prime.

 

[gabe600r]

I already changed the coolent temp sensor and that didnt change it and as for the fuel pump my old car had the stock fuel pump when this started and this one has brand new walboro 255 so im thinking maybe a bad injector how can i test the injectors even tho im not sure thats what it is I have had to take fuel line apart and it still had presure

 

[BlackTsi1992]

Are you running an afpr with that 255?

 

[rcarbajal4]

It could still be coolant temp sensor. I changed mine out but turned out to be the plug itself was damaged. Pulled a pig tail off a junk car and problem solved. May also be clogged fuel filter.

 

[gabe600r]

running stock fuel pressure regulator and has a new fuel filter also did replace the plug on coolent sensor but really dont think is that like I said problem started on my old car I also have gm mas conversion was thinking maybe maf is bad but wouldnt that throw a code my car does throw a code for the coolent sensor guess gonna have to check the wires

 

[92AWDHX40]

Could be a bad ecu, plugs wires, the wrong switch made double check it could be a boost leak, or coil pack again could very well be the ecu you picked or the wiring you did doesnt add up, check it again use vfaq you, youre not sure. Check the mas sensor too, any codes.

 

[gabe600r]

fixed the problem when I was messing with something else had the tps sensor unplugged

 

[got_psi]

Ha this oddly answered a question i had about ECU swap so thanks !