[stangman67]

Hello, I just recently purchased a 89 5.0 LX convertible. Dont know much about fuel injection but I suspect that I have a clogged injector or 2. Rough idle, sometimes stalls, rich at the tailpipe, poor throttle response and under powered. Newer engine and it runs great when you accelerate but seems under powered. Also spits and sputters going down the road at low speed and low RPM. Any other opinion as to what may cause this. Running sufficient advance in timing.

My question is,, If I am going to replace injectors anyway, should I step up to #24 lb injectors since I will be doing some mods to the engine to get more power ie headers, exhaust, gears etc. But nothing drastic yet. Will my ecu support #24 injectors and a 70 or 73mm MAF throttle body? I understand that I can get away with a larger throttle body as long as its calibrated to the #19 injectors. I dont plan on keeping the car long, just want a nice driver with a bit more power. I read that the stock 5.0 for 89 has 225 hp but this one seems somewhere in the 150 range, but could be because of the extremely tall gears. HELP, suggestions. Thanks much guys.

 

[sniperd]

Your good with the stock injectors, 24 would be a waste with what you have planned. I ran the stockers with a full bolt on motor just fine.

Just take them all out and clean them, I doubt you need new ones. Do you have a check engine light on? Check your fuel pressure, double check that timing again and make sure you have your TPS voltage set and everything good there.

 

[need4spd90]

start by checking for trouble codes..injectors are an expensive waste of money if they're not the problem..no sense in replacing stuff that aint broken..
DIY KOEO/KOER/Cylinder Balance Self-Test Procedure

 

[stangman67]

Guys, thanks for the info. No check engine lights. Timing is ok. I will check fuel pressure. It should be around 40-45 right? I will also clean injectors. Tell me more about TPS voltage? Thanks

 

[spdjnky_42]

TPS v should be around .98 but if your idle is at 800 or close then your probably fine there. Run the codes doing the self check test. FP should be around 40#. No need for 24# and the MAF has to be programmed if you switch. A 73 meter is always a plus. Pull your injectors have them bench tested. Have you done a tune up and tried cleaning your MAF?