92 buick roadmaster, still fighting surging idle after timing chain swap.

[rnj]

Ok, so I finally swapped the timing chain, to try to cure a surging idle problem. History of what has been done is in the thread/link below. To make story short: When car is started, it will surge from 500-1000rpm. and has a miss at light throttle. in the passing gear, car feels and pulls strong/smooth. b4 the timing chain swap it would jerk pretty bad. Any help will be greatly appreciated. Things I have to do is make sure timing is set right, and refresh the gas. i seriously can't remeber when I took it apart to do the chain, and then it sat for quite a while b4 I could complete it, but symptoms are still there. Starting to get stressed!

Replaced items
tbi gasket
egr valve
plugs/wires/cap/rotor
o2 sensor(keeps throwing 44? code for lean condition)
map sensor
iat sensor
thermostat
Fuel pump (am going to test pressure again for s!@ts and giggles)
timing chain


tested items
tested tps
tested ignition module 3 seperate times


http://www.automotiveforums.com/vbul...d.php?t=637655

[rnj]

Well, I went through with the timing chain because when I would set the timing to 0* btc the car would not fire. I had to set the mark advanced (seriously) about 2 inches to the left of the whole timing tab. So I thought obviously the chain is stretched, and maybe the engine was messing with the pcm, and hunting for the correct idle. I did every thing that supposed to cause a surging idle, to no avail. We first had the pump replaced about 2 yrs ago when this started acting up. So I was solid on the fuel pump not being the problem. So I finally started thinking pump, so I bought a pressure gauge, but the actron "t" fitting is supposed to bolt to the supply line at the throttle body. Well there is no room for the fitting to fit no easy way to bend line. It took me a while to figure something out, and low and behold, when I attached the gauge i got 6psi. All this time and it was just the pump. Just put in new pump last night and guess what no more surging, long crank times, and no DTC 44 lean condition. Car has...who knows how many miles. the chain I swapped was after market, and considerably stretched. Timing is set at 2* BTC and car responds so nice. Hope fully this will help some one in the future. If your symptoms sound like these or even close, CHECK fuel pressure regardless of new fuel pump or fuel filter. May even have a collapsed or pinched fuel supply line.

[rnj]

fuel pressure tester from Actron part number CP7817