97 454 won't run right. PLEASE HELP!!

[fintelmales]

I need some help please. Last month I bought a sweet 97 K2500 x-cab, long box, 454, auto. Love this pickup so much but it LIVED in the shop ever since I got it home. I bought it 250 miles away and it drove home fine. It did start hard when I was picked it up, but ran good on the way home. Ther service light was on so I took it to my mechanic and had it checked. They put on a new mass air flow sensor and something else (can't remember) and took it home. It ran worse and started worse so I took it back in and they did the distributor, cap, rotor, etc. started great once, then started worse then before but ran ok. Went to go pull empty gooseneck and does on the road after two miles. Ugh! Found out this time it was the ignition coil and some other little thing. They towed it in and then I had them do a fuel pump just because I was sure that was a lot of it. Also found the mass air flow bad so did another. They also put in a new ignition switch and harness. Come to find out the mass air didn't have enough power so did a new computer AND IT STILL WON'T RUN RIGHT!!!
The issue it has is starting soooooo hard and either runs like a NASCAR or sputters. The running issue is very random too. If you romp on it it shakes and hesitates and it might dies or take off like a rocket. The pickup is damn sharp and isn't all rusted up. Only has 170k on it so I'd love to keep it around for A LONG TIME, but I'm so pissed at this rig!! Do ANY of you guys who are WAY smarter than me help? My mechanic is at a loss and I don't know what to do!

 

[Lextech]

It is very common for the injectors and fuel pressure regulator to act up on the 7.4 trucks. I have no personal experience but, It is a very common issue on the forums.

Jeff

 

[454ss]

first, you need a new mechanic, then you need to check cam wear, fuel pressure regulator and injectors. does it start hard after being warm then shut off and started a half hour later? some 454s had bad cam cores that were soft and killed lobes, stock injectors are junk and fpr is very common to fail. also at that many miles timing chain and distributor/gear most likely need replacement.

 

[HIGH BOWTIE]

Could be completely wrong but maybe timing is off? Maybe someone replaced the chain and have it off just a tad? Had that hard start problem on a Honda when I did the timing belt and didnt check the marks on the crank but never messed with a chain. Again I could be way off on this one

 

[fintelmales]

Thanks guys. I really appreciate it!
I'm going to do the injectors and FPR first of the week. Do you have any recommendations on brands for the two? I have a Napa, Car Quest, and independent parts store in town. 60 miles from Chevy dealer.

 

[LoudnLifted88]

injectors and fuel pressure regulators are usually the main cause of hard starting mine are going bad and it takes a few seconds to start after its been sitting for a little while

 

[454ss]

fiveomotorsport.com is the place to get injectors, 300 a set instead of 200 each for delco replacements.

 

[VorTecxas]

Injectors and/or FPR, I'll almost guarantee it's your problem, as well as your so-called "mechanic".
I got a used (but tested and guaranteed) set of LS1 injectors from an eBay store for $150. And an FPR from the same place. So far have 2,500 miles since the swap with zero problems, and I've ridden her pretty hard. Just be careful who you buy from, make sure their feedback is good and they have some sort of guarantee. Bosch is your best bet on injectors. My FPR was a Delphi

 

[mchlgriffith]

u can get a set of bosch 4 hole injectors from a place called fuelinjectorman.com to replace the stock single hole injectors, and get the regulator and plenum gasket from any parts store. im going to swap mine out sometime this month.

 

[fintelmales]

Are they hard to swap out? I'd like to do it myself if possible. I've done all kinds of stuff on 350tbi's but this Vortec multi-injector unit scares the out of me. Any feedback would be very helpful.
I see Bosch 4 hole are good injectors, as well as fivemotorsport.com. Any other injectors you'd recommend?