Need some advice PLEASE

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   I am new here. I have a 87 fiero 4 cylinder. Replaced a faulty fuel pump and car ran excellent for one day. 
Now it seems the duke starts and idles good in park revs in park also, sounds good.
As soon as you put it in gear and give it throttle it pops and backfires through intake. Here is a list of thing done.
New plugs ac delco
New plug wires
New map sensor
Compression check 125 all 4
Fuel pressure check 20 psi
Checked catlitac for blockage
Opened valve cover to check no problems 
I just dont get it. I am going to check coils and pim tommorw but do not think it is the problem. Wish at this point i could just drop a weber on it but dont think its possible.
Any and all help is much appreciated. All things listed was done after the problem except fuel pump. No codes read either.
hopeful for replies.

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Chris38 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 25 May 2016 Location: Alabama Status: Offline Points: 6	Post Options Post Reply Quote Chris38 Report Post Quote Reply Topic: Need some advice PLEASE Posted: 25 May 2016 at 4:46pm
	I am new here. I have a 87 fiero 4 cylinder. Replaced a faulty fuel pump and car ran excellent for one day. Now it seems the duke starts and idles good in park revs in park also, sounds good. As soon as you put it in gear and give it throttle it pops and backfires through intake. Here is a list of thing done. New plugs ac delco New plug wires New map sensor Compression check 125 all 4 Fuel pressure check 20 psi Checked catlitac for blockage Opened valve cover to check no problems I just dont get it. I am going to check coils and pim tommorw but do not think it is the problem. Wish at this point i could just drop a weber on it but dont think its possible. Any and all help is much appreciated. All things listed was done after the problem except fuel pump. No codes read either. hopeful for replies.

Capt Fiero Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Founding Member Joined: 12 February 2007 Location: Canada Status: Offline Points: 4039	Post Options Post Reply Quote Capt Fiero Report Post Quote Reply Posted: 25 May 2016 at 5:20pm
	This sounds kinda dumb and basic, but I have seen professional mechanics make mistakes on plug wire locations. I don't have the info handy, but maybe someone with a running normally Duke Fiero can post up where they have their wires. I had an 88 Duke for a few months, and quickly found out there was a public confusion on which plug connected to which post on the coil packs. This is the photo I went by and found it confusing back then as the Coil Packs lugs are not in a straight line.
	Capt Fiero 88 Fiero GT 5spd V6 Eight Fifty Seven GT V8 5spd.

Chris38 Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 25 May 2016 Location: Alabama Status: Offline Points: 6	Post Options Post Reply Quote Chris38 Report Post Quote Reply Posted: 25 May 2016 at 5:52pm
	Dont think it was a possibility. I done one at a time and car was running good with the ones on it before problems started. But i will most definitely recheck.

ARTIC-1 Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: 14 October 2009 Location: Canada Status: Offline Points: 434	Post Options Post Reply Quote ARTIC-1 Report Post Quote Reply Posted: 26 May 2016 at 6:51am
	Hi an Welcome I have an 88 Duke with the Coil pack,the Thing? That sets your Ing timing is a sensor that bolts in the side of the block an can give you trubble some times,looks like an over grown led pensal an can crack.all so the TBI injector can gum up,still lets some fuel in but not the right amount an make the motor run lean or Ritch,it messes with the computer,there are other members here that may have better in put than me,The TBI has a small screen in it,one Screw holds it in, check that,carefully there's O rings in there that go hard an can leek,should replace them,good luck hope this helps
	SNOW MAN 87-GT/AUTO-2.8_ WHITE 88-TTop/ Duke-2.5. RED

beken Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 12 February 2007 Location: Canada Status: Offline Points: 1464	Post Options Post Reply Quote beken Report Post Quote Reply Posted: 26 May 2016 at 1:17pm
	It sounds like your car is starving for fuel. Have you replaced your fuel filter? I've changed mine every 5 or so years. On a Duke engine, I think it sits right on top.
	Beken (aka Ken) - bekentech@westcoastfieros.com Original and still the owner of an 85SE 2M6 4spd

Dr.Fiero Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Post God Joined: 12 February 2007 Location: Canada Status: Offline Points: 1726	Post Options Post Reply Quote Dr.Fiero Report Post Quote Reply Posted: 28 May 2016 at 6:23am
	On the '87 it was moved down below where the V6's is. Get a scan tool, and see what your MAP is reading (you need to know what the voltage vs MAP is). Might be dying when a load gets imposed, and the vacuum drops.