Opinions wanted [Tuning shop or repair shop?]

[ChrisFlo]

Hey guys-

I have a 98 gst with the following mods:

Autometer Boost guage
3" Dejon Tool Intake/K&N Filter
NGK Spark Plugs/Wires
Greddy S BOV
Hallman MBC
Walbro 190
Bullseye T04B V-trim
3" ATR 02 Eliminator DP
Magnaflow high flow cat
custom 3" catback
JR FMIC/ 2.5" piping

Tomorrow I have an appointment to take the car in to have 650's and an SAFCII installed. However, the car has been running poorly, with hesitations before 3K. I understand that this could be due to the fact that I'm not tuned, but realize that it may have nothing to do with tuning. I've been working to resolve this issue, but haven't yet. Here's my question.

Would it be best to take the car in and have it tuned to see if that is the problem, or would it be best to take it to a repair shop to see why it's running poorly before I have it tuned? I'm also planning on selling the car once I get it running, and am considering just taking it back to stock parts. If I went this route, I wouldn't even have the SAFC and injectors installed tomorrow. I'm really confused. Give me some opinions.

 

[The_EE]

have you done a boost leak test? That could be part of the problem. It could be a number of things but without more info it would be hard to tell. Does it totally go away after 3k RPM's? I dont see an adjustable fuel pressure regulator on your list of mods. the 190 should be ok without it but if your stock regulator is going out, it could be drowning your plugs and causing the hesitation. If that is the case then it would be worthless to tune the car with the afc because everything will change when you get a good running stock regulator or a aftermarket on the car, if that is indeed your problem.

how do your plugs look? Whats your vac at when you are at idle?

 

[ChrisFlo]

have you done a boost leak test? That could be part of the problem. It could be a number of things but without more info it would be hard to tell. Does it totally go away after 3k RPM's? I dont see an adjustable fuel pressure regulator on your list of mods. the 190 should be ok without it but if your stock regulator is going out, it could be drowning your plugs and causing the hesitation. If that is the case then it would be worthless to tune the car with the afc because everything will change when you get a good running stock regulator or a aftermarket on the car, if that is indeed your problem.

how do your plugs look? Whats your vac at when you are at idle?

I have done a leak test and didn't find any leaks. The hesitation does seem to completely go away whenever the car is over 3k. Plugs were just recently changed and wires are about 7 months old. My vac at idle is around 17 or so.

 

[The_EE]

I would say try testing out your FPR. If you were local I would let you use my stock one to see if that was the problem. If you can find test it and see and if it is not working correctly.

 

[ixsaves13]

Like most people are telling you to do... It would be best to fix any problems before any additional mods are done. It only increases your choices for things that could go wrong. If you're going to sell the car, you might as well not invest more money in parts.

Good luck!

 

[bluetlr2001]

Dont mean to but in but how do you test the fpr? do you just use a fuel pressure tester or is there away to test the fpr itself. Because mine does the same thing and ive got a 190 with a rewire. But mine doesnt go away at any rpm. Its just randam.