jpop8807

Today after the UFC fight me and the wife did some spirited driving. I had no problem getting thru first and 2 gear. When i was in 3rd around 5 to redline my car started hesitating. As if a person was running and had to let off power to get air. Kinda like it felt as if i slightly let up on the gas pedal and then pushed it back down. Which i didn't. Has anyone experienced this or might know what this is. Like I said 1st n 2nd had no problem i think. Just third it didn't feel like it had anymore power for a few moments in the upper rev range. All my gauges seemed to be fine. And when i had the car checked out everything seemed fine. Only engine part that needed to be changed was the cam gasket. If you don't understand what i'm talking about and you live in San An, Dallas, Austin area we can meet up and you can drive it.

jpop8807

OH ya everything about the car is stock. It might have a 3 inch cat back I know the muffler is magnaflow. I just found this article. Could this be same thing with my car?

https://rennlist.com/forums/944-turb...st-cutout.html

blown 944

Check your plug gap. It may need to be reduced. If it happens when it's cooler out then I'd say that plug gap would be my first thought bc the air is more dense and cylinder pressure is higher as a result.

jpop8807

That could be it is cooler tonight. Whenever I get some money ill do the ignition package from lindsey.

jpop8807

Well checked the plugs thier good. Took her out for a spin same problem. It only has that hesitation of power in the higher gears no problem getting thru 1 n 2nd. Third and for gear starting at around 3500 it pulls hard hesitates then pulls hard again. The hesitations are really fast maybe like 2 seconds or less of hesitation then hard pull the shorter hesitation. Over and over again. Like i said in the first post you live in texas I can let you drive it to see what i'm talking about.

Ronin-951

Sounds like a Coil problem, start with new wires, plugs and cap [stock stuff, not the fancy pricey crap esp. the plugs, copper is best] - probably needed anyway - and add a new Coil if the problem persists.

sns951

You've said there's no problem in 1st and 2nd ... when do you shift? does the problem present at 5000 all the time, or only under a range of load conditions (gear/speed dependent)?

I'm a novice, but maybe this'll help someone else diagnose. also, 3500 is about when my stock 87 starts spooling, when you said it pulls hard, then like you suggest 5000 is wastegate ... i'd check the WG for sticking

Scott H

I'd definitely take a look at the cycling valve (brown circular thing with three nipples on it and an electrical connector under the intake manifold near the firewall), sounds like it may have cracked and is letting boost pressure leak out. It may be less noticeable in 1st and 2nd due to the lack of time spent on full boost in those gears.

jpop8807

Sorry correction yes your right it starts the mini lags at around 3-3500. And yes its funny its only in the higher gears. This is under full load as in peddle to the floor. I have no problem flying thru the first 2 gears but then the gears that it takes a little longer to reach redline area is having this problem. It just started the day I wrote about it never had the problem before. I'll check it out when i get finished with guard.

jpop8807

Ok on another note was driving shifted down into 3rd gear to see if my problem was still there...it was. But when I eased on and I was at 1 or I guess 2 lines over one it had no problems only at full boost foot on the floor did it do the same thing. Before it did it at lower rpms due to flooring it but gettin it to about 4500 then flooring it was completely differnt almost a jerking motion. After that I smelt some burnt oil when I slowed down with the windo down. Could my turbo be the problem?

sns951

i'll lead off with the warning i have a beginner's knowledge, but...

pushing the turbo hard, so demanding high flow at high shaft speeds, pushes the compressor into choke. max airflow is limited by the comp wheel. if the turbo is pushed too far beyond its operating range, namely if there is a pressure difference between comp out and turbine in in excess of the bearing sets' design, then the seals are liable to leak oil. maybe that's how oil got into the exhaust for you to smell? (or 20 yrs added up ... piston rings, journals, ect)

if the engine is stock, no franken-turbos or hot-housings or ecm remaps or waste gate shims, then this shouldn't have been the case. the k26 flows plenty for a stock engine.

i would be inclined to investigate the wastegate pressure loop and its controller.

if you really can't stop thinking the turbo's at fault (what's your mileage?) then a non-destructive bearing test id shaft end-play.

does the engine cut back with the same behavior at redline? i don't have as much experience with fuel systems, but the other half of a/f could be the culprit ... someone else please chime in, too!

Bri Bro

Second vote for cap. rotor and plugs and swap out coil. I had a cracked cap, did the same thing. Anything in the ignition path will do this.

jpop8807

Got it will hit that up on my next paycheck. Should I just buy the replacements or should I get a set from lindsey? I will eventually add more stuff to the car once I get it running right and so forth.

Ben951S

It all depends on what parts/quality/price you want to pay. I would compare pelicanparts, lindsey, maybe paragon and then see if rennbay has anything.