'97 Startup Problems

[IceTray519]

First post, and its for the girlfriend, haha.

We picked up a nicely kept 1997 GTP supercharged this summer, car works good, relatively clean, easy user. It's run well up until recently. The car is tuned, AC was deleted, has been inserted again though. (No lines hooked up)

Now, as of two weeks or so ago, the car has been struggling to turn over, it just cycles hard, coughs when you let off the ignition. I've also noticed that the symptom can be eliminated by simply holding your foot on the accelerator just a tiny bit, however doing this, also causes it to surge hard when it finally gets going. Keep in mind, you're only lightly pressing on the pedal, but it surges to almost 4k rpm.

Occasionally there is a small odor after ignition, but its also in a small enclosed garage where its being worked on.

This is her everyday driver, so between working on an Fbody and work, I wanna get this thing running solid for her as soon as possible - it was completely dead the other night, she couldn't get it to turn over.

(MAF has been suggested as an issue, however the car only has this problem if its been sitting for a few hours, it starts up fine if its still warm)

Edit; 310,000km

[Fivefingerdeathpunch]

I would remove the throttle body and clean the piss outta it. Then clean the MAF sensor aswell.

I'd also prime the pump once or twice and then remove the vacuum line going to the fuel pressure regulator. If you smell gas or see gas drip out, the diaphram inside has failed. Thus leading to longer cranks and slow/choppy starts.

[IceTray519]

I would remove the throttle body and clean the piss outta it. Then clean the MAF sensor aswell.

I'd also prime the pump once or twice and then remove the vacuum line going to the fuel pressure regulator. If you smell gas or see gas drip out, the diaphram inside has failed. Thus leading to longer cranks and slow/choppy starts.

Well, this morning I was with her when she had to leave for work, car didn't start regularly. So I had her hold the accelerator a little bit, and it started right up. However there was a strong smell of gas right after startup, so I should probably be looking to replace the fuel pressure regulator?

[Scottydoggs]

pull the vac line off the fpr and sniff for gas. its the round thing on the fuel rail with a vac line to it.

and you clean the TB yet? if not get to that.

[IceTray519]

I've been working on it since she got it, the last owner unplugged a lot, plugs dangling all over the engine bay, lights flicker, HVAC vents don't function.

So I'm going to pickup a new FPR, and start cleaning out the AIC and TB. Might have her car tonight, hoping to see results from the poor thing

[Scottydoggs]

please dont toss parts at it. thats a waste of money. if the vac line smells of gas, then change it, dont wast your time or money if theres no smell.

do clean the tb up tho, remove the maf first, as nothing should touch that but maf cleaner.

the plugs all over, i must say we all have like 3 plugs to nothing. its normal. by the battery, the fire wall, the rad support area. all spots with plugs to nothing.

the hvac, whats up with it? air flow direction not working, or hot one side cold the other?

[IceTray519]

Alright - the HVAC doesn't direct air, I assure something is also unplugged

[Scottydoggs]

theres a vac line off the top of the sc, it then leads to the pass side firewall, make sure its hooked up, then follow it down the fender near the battery looking for other damage.

[IceTray519]

theres a vac line off the top of the sc, it then leads to the pass side firewall, make sure its hooked up, then follow it down the fender near the battery looking for other damage.

I appreciate the help you've provided thus far. Unfortunately I must be blind, I cant find the vac line you're talking about. Would you happen to have an exploded diagram that could better show where it should be? I found a line with a red plug that's sitting on top of the cross member in the front..

[Scottydoggs]

under the fuse box, the T some cars have. changing the battery sometimes you crack the line.



the tree a top the sc has 3 ports, one leads to the pass side fire wall. as seen here. that same black hard line runs down the fender to under the fuse box.

[IceTray519]

Alright, thanks for the visuals. I havent had a chance to get out and look at it - been about -30C here, and I've got a dead Fbody in the garage, so I'll have to bear the elements sooner rather than later and see if I can locate the lines.

[BillBoost37]

Line should be cruising around the strut tower on the passenger side and going to the plastic thing aka manifold on top of the SC. Easy to find..as the brake booster line is hooked up next to where this belongs.

Keep asking questions and feel free to toss up pics of stuff that looks odd or isn't connected. We'll ID it for you and tell you what you need or can leave alone.

[IceTray519]

Line should be cruising around the strut tower on the passenger side and going to the plastic thing aka manifold on top of the SC. Easy to find..as the brake booster line is hooked up next to where this belongs.

Keep asking questions and feel free to toss up pics of stuff that looks odd or isn't connected. We'll ID it for you and tell you what you need or can leave alone.

Thanks, it's quite helpful, I just dont have the time to rebuild one car and figure out the other haha.

Anyway I got out there just now and looked, all the lines are hooked up properly - unfortunately. So that puts me back at the starting point. The red plug (looks rubbery) sitting under the front header, seems like its resting accross the kmember, is something I wonder about. I couldn't get a picture of it, my hands were so cold my phone thought I didn't have fingers.

I'll try to warm up a bit and head back out to try and get a picture.

Knowing the lines are all fine, what else could be affecting the vents functions?

[Scottydoggs]

if all the vac lines look ok under the hood, its either the climate control, or the black box under the dash that the line from under the hood plugs into.

[IceTray519]

if all the vac lines look ok under the hood, its either the climate control, or the black box under the dash that the line from under the hood plugs into.

I'll have to look into the black box then.
This was the plug I was talking about though; it's just kinda hanging out, can't find a socket to plug it into. Thought maybe it was related to the vents not working.

[Scottydoggs]

no idea wtf that plug is.

wait, maybe its to a block heater. look at the freeze plugs it may fit on the heater if theres one. the other end of it would have a 110 outlet plug on it if its a block heater.

[BillBoost37]

Yeah.. no idea on a red plug in that area either. And I've been in/under too many not to recognize it. Unless it's for the air pump that came in some. Mostly 00+

On the Hvac.. it's the vac line. 100% positive unless your thingee in the dash is broken.

[Sven the Sexman]

Yeah.. no idea on a red plug in that area either. And I've been in/under too many not to recognize it. Unless it's for the air pump that came in some. Mostly 00+

On the Hvac.. it's the vac line. 100% positive unless your thingee in the dash is broken.

Plug goes to a block heater.

HVAC...I'm with Bill.

[IceTray519]

Alright, I'll settle on the line. Next time the car is here, I'll have to pull the battery, and just overall check the line for leaks. Is there any way to check it? Other than taking it out pushing some air through it and listening for a leak?

Now to the original problem, the startup.
No smell of gas from FPR line, TB clean. No MAF cleaner though, visually it looks clean, and it still won't startup without accelerator pressed a bit.

I have a spare MAF sensor from a 3800 series RWD (v6 camaro) its brand new, but malfunctions out of the box, figured I'd still hang on to it, with the broken MAF in the Camaro it started up fine, but had a very very rough idle (Regular signs of a bad MAF) and would stall in under 40 seconds if your foot wasn't holding the acclerator to keep it above 800RMP, however it had no startup issues. This leads me to believe it may not be the MAF either, because once the GTP goes, it idles perfectly, not a single hiccup, idles, drivers, everything is fine. It's just the initial startup, and it has to have been sitting long enough to cool down completely.