starting problem
Thread Starter
Intermediate
Joined: Jan 2013
Posts: 45
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starting problem
Hello, if there's anyone out there that can help me with this issue it would be greatly appreciated. I have a 1987 corvette and just installed a motor from a 1990 corvette with only app. 1,000 miles on it, not a rebuild but actual. Problem is the mechanics working on the car say they're having a very hard time starting it in the mornings, it takes maybe 7 cranks before it starts and they said the MAF reading is stuck on 3.4, it will not fluctuate at all. They are telling me to get a new maf but the one on there has only 500 miles on it and it is a high dollar one, I paid $325 for it and I am reading that the cold start injector shouldn't be necessary for me as I live is Southern Calif. Please if there is anyone that can shed some light on this problem Please let me know. Thank You and "GOD" Bless.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
With your setup I'd say the 7 cranks to start is normal. What you think is cold is not what the engine thinks is cold... I assume you're using the original '87 ECM, which thinks the cold start injector is there and functioning.
I would check the wiring of the MAF to make sure you have everything hooked up as necessary. I recall a change in the MAF connector, but don't know when that happened, so that might have something to do with this problem.
I would check the wiring of the MAF to make sure you have everything hooked up as necessary. I recall a change in the MAF connector, but don't know when that happened, so that might have something to do with this problem.
Oil Producer
Joined: Apr 2014
Posts: 9,363
Likes: 2,734
With your setup I'd say the 7 cranks to start is normal. What you think is cold is not what the engine thinks is cold... I assume you're using the original '87 ECM, which thinks the cold start injector is there and functioning.
I would check the wiring of the MAF to make sure you have everything hooked up as necessary. I recall a change in the MAF connector, but don't know when that happened, so that might have something to do with this problem.
I would check the wiring of the MAF to make sure you have everything hooked up as necessary. I recall a change in the MAF connector, but don't know when that happened, so that might have something to do with this problem.
Can anybody recommend a professional C4 tunner so this member can give them a call? I am thinking that its got something to do with the difference in how the cold start injector was handled between the 87 and the 90. (edit: <<--- actually technically they are supposed to be the exact same)
actually...wait...which computer are you using? the 87 (1227165) or the 90 (1227727)?
technically, those ecm's are the exact same ....just one is mounted inside under the breadbox and one is mounted outside above the battery.
IF you are using the 87 computer, is it possible that you have a modifed chip in it for something that was done to the 87 motor that is not done to the 90?
Last edited by VikingTrad3r; Oct 4, 2016 at 11:52 AM.
Racer
Joined: Apr 2013
Posts: 435
Likes: 4
From: Guilford NY
(edit: <<--- actually technically they are supposed to be the exact same)
actually...wait...which computer are you using? the 87 (1227165) or the 90 (1227727)?
technically, those ecm's are the exact same ....just one is mounted inside under the breadbox and one is mounted outside above the battery.
IF you are using the 87 computer, is it possible that you have a modifed chip in it for something that was done to the 87 motor that is not done to the 90?
actually...wait...which computer are you using? the 87 (1227165) or the 90 (1227727)?
technically, those ecm's are the exact same ....just one is mounted inside under the breadbox and one is mounted outside above the battery.
IF you are using the 87 computer, is it possible that you have a modifed chip in it for something that was done to the 87 motor that is not done to the 90?
Oil Producer
Joined: Apr 2014
Posts: 9,363
Likes: 2,734
oh interesting, before I posted that I googled it and the chart I found said they were the same the only difference was one was mounted inside and one was mounted outside
edit. maybe not! i goofedup my reading.
http://tpiparts.net/ecms_and_proms/
edit. maybe not! i goofedup my reading.
http://tpiparts.net/ecms_and_proms/
Technically, they are NOT the same.....the older one uses a Mass Air System, the newer one is Speed Density. Completely different. Need to know what the OP is actually using, and did he install the cold start injector? That is NOT ECM controlled by the way......
Last edited by VikingTrad3r; Oct 4, 2016 at 07:29 PM.
