No Throttle Response / Then its fine

Gentlemen:

Cold to Cool start issue.

I will start it, running it for 5-10 min, I will hop in put it in gear, it will initially bog and occationaly pop in the engine, happened twice. No throttle response like its an old quadra jet.

After about 2 min of driving, the throttle response is normal, it drives like it should.

Opti, wires, plugs done at 85k. Its got 100k on it now.
Fuel injection cleaning done at 95k.

Any ideas I should look at? Its not that bad of an issue as she is old and I can take my time get going then its back at full strength with engine running perfect.

Thanks for any input

Clean the MAF.

Or unplug it and see if it runs ok in speed density mode...

I'd start with Crovo's MAF cleaning

Assuming you checked all the vaccuum / intake / emission lines etc

If it doesnt fix try the ECT sensor (in water pump)

The coolant sensor acts almost in reverse of your problem
When sensor body was broken (& epoxied together by my A+ mechanics helper), mine started fine, but when warmed up it did what yours is & wouldnt restart (when up to temp) without pedal to the metal.

Theyre not expensive & you dont lose alot of coolant if your quick.....& lucky

Well I tried the MAF cleaning today. Got the stuff at the store, took it out, cleaned it, checked the connections, checked the vacuum lines dont see any cracks.
Same result , a 5 min warm up, hit the gas moderately, it bogs, then a carb esque pop under the hood, but its comming from the driver's front by the air cleaner box/filter pack.
With in a min or two, its perfect.

ECT sensor is a the next recommendation? I am ordering up a A/C delco MAF as the one in the car is orginal and its smart to eliminate the potential issue if any with it.
I did not see any tell tale signs being wrong with it, but it is 17 yrs old.

Any more ideas? Thanks guys

IMO ordering a MAF is overkill, but if your more comfortable that way...so be it.
Any access to someone with a scanner or a shop manual? It'll save you some $

Got a buddy of mine who is a A/C Delco rep. So the deal on the MAF is insanely good at only $90. Why not, its old? Eliminate the potential.

We are going to run a scanner on it this weekend see if it will pick up any problem. It may not be triggering the CEL.

Thanks

Fuel Pump.

Was not reading more than 10psi at start up and when the car was at idle it would occillate? between 15-28psi in gear with the fuel pressure guage running on it.
That would explain the irregular starting I was begining to have and the fuel starvation,throttle response issue at low idle near a dead stop.
So.. this will be fun... Fix and see where we land

The wiring harnesses for our fuel pumps are notoriously problematic.

It seems the General got particularly cheap building that particular run.

I'm not saying that this is your cause, but don't overlook scrutinizing that harness if you suspect your fuel pump.

Back in action.. good to roll.

Fuel pump was junk.

A bad harness still may have been a contributing factor toward the early failure of your fuel pump.

Line voltage drop from an inadequate gage &/or dubious quality wire run will cause the amperage to spike, which is not good news for your fuel pump.

You can not circumvent ohm's law.

Back to the garage.

2nd fuel pump went in just 8 weeks. Was only pushing out 17psi and with throttle pegged, it was 21. Just starving for fuel.

THEN.. as some of you mentioned... ECT. 
I got some learning to do.. that sensor is acting up. More work to get running right. Did the right side cooling fan motor last week as the temp kept spiking, then did a coolant drain. FUN FUN... But no complaints, as driving it 24/7 for the past two years has been a blast

So did you replace the sender with the pump?
What brand pump?

You can test your ECT below...you wont know if its right on but you'll know if its out of range
Easiest way is with a spare connector & some leads

Wraith'SS wrote:

Back to the garage.

2nd fuel pump went in just 8 weeks. Was only pushing out 17psi and with throttle pegged, it was 21. Just starving for fuel.

THEN.. as some of you mentioned... ECT. 
I got some learning to do.. that sensor is acting up. More work to get running right. Did the right side cooling fan motor last week as the temp kept spiking, then did a coolant drain. FUN FUN... But no complaints, as driving it 24/7 for the past two years has been a blast

This will solve fuel pump issues. Lots of people (including me) use these kits on Turbo Buicks to 500+ HP. When ANY of my B-body pumps die they will get one of these pumps + a hotwire kit. These are of the highest quality

http://www.racetronix.com/RX-BLT1-FPKG.html

V8Killer wrote:

Wraith'SS wrote:

Back to the garage.

2nd fuel pump went in just 8 weeks. Was only pushing out 17psi and with throttle pegged, it was 21. Just starving for fuel.

THEN.. as some of you mentioned... ECT. 
I got some learning to do.. that sensor is acting up. More work to get running right. Did the right side cooling fan motor last week as the temp kept spiking, then did a coolant drain. FUN FUN... But no complaints, as driving it 24/7 for the past two years has been a blast

This will solve fuel pump issues. Lots of people (including me) use these kits on Turbo Buicks to 500+ HP. When ANY of my B-body pumps die they will get one of these pumps + a hotwire kit. These are of the highest quality

http://www.racetronix.com/RX-BLT1-FPKG.html

I'm still planning on running one of their fuel pump harnesses in the DGGM. Heard nothing but good things about them, just trying to get some other stuff out of the way as it runs great the way it is now...

X2 on the racetronix. When I drop my tank to refurb the sender, I'll be going that route.

Just added that to my DD...40PSI ROCK solid cruising

Once again.....dont forget sender.....mods are required

JUST the addition of the harness (to a good pump & sender) is a step in the right direction

Full voltage to pump....FTW

Thanks for the motivation, Steve!

I MIGHT just replace everything. Brandy new parts. Pump, sender, etc. I think it was all about $400 + the harness?

I noticed that there is the option of getting a body ground upgrade with the Racetronix FP harness...I wonder if that's worth doing?

BTW, here's the direct link:

http://www.racetronix.biz/itemdesc.asp?ic=FPWH-004&eq=&Tp=

The body grounding option is a 12" pc of wire lugged & sleeved with adapter bolts for the battery
Not a bad deal for $12 as your exisiting wire is tiny
(remember how many problem solving tips start with "check your grounds".... )
I had already installed the battery/motor/body cable kit so I didnt bother



BTW right now, I'm running the pump with the existing harness
New harness is in place but not connected on either end
When I was originally working on the car I didnt want another variable (new pump & wiring) in the picture.
Now its just waiting for a free day to connect

Stranded again today.

Plan to check harness as we did fuel pump#2 plus ect sensor and it ran pisssah on Friday and Sat. Today went out drove 15 miles then it shit the bed, stumble and rumble then dead. So .... Needless to say my DD has hit it's first month of trouble in two years , can't complain.
Just hoping we figure out wtf is causing to to die out.
Also printed out the chart from above and cross ref it. On the money Friday nite. So this is a effin head scratcher. Least the tow truck drivers were cool and wondering why I was driving it out to a farm stand where it died on a dirt parking lot? I was laughing saying , you have one, you understand... DRIVE IT:D

Alot of fuel pump / sender problems interact & are hard to pinpoint
My sons car lost the back flow valve on top of the pump but we saw that with a gauge
Primed right up & dropped right off...immediately
Ran fine but would cutout randomly....could hit the hot wire & prime & go....finally it gave up
Gave him the confirmed good pump & sender out of my DD & all is good

Before I went that route, I checked the coil & wiring, swapped the ICM ( a couple of hot=fail items)

No update today. The effin thing is running fine AFTER it was towed.
Only code showed was p003? Random misfire.... Tested the car, ran it two hours each of the past few days. Drove it 20 miles.
I have no clue what's up.
The random misfire code occurred as it stalled out, chugged and died Sunday.

At this point I am pissed if I have to replace a new AC pump with this Walbro kit/harness, but that sounds like I could rule out my issue potentially but just doing it and be done, move on .

MSD opti done at 86k, it's got 103k on it now, so I don't think that could be the problem, but that random misfire code is making me question things.

Any suggestions that I could throw at it would be great as this breaking down gremlin is bothering the hell out of me for such a bullet proof car.

Sorry to bother you all... Appreciate it

Do you have a fuel pressure gauge?
Drive it until it dies & throw the gauge on to see if its fuel or not
A bad fuel pump WILL come back to life & fool you.....a couple of times.....before totally stranding you again

So....if it dies, and you have no pressure. Hit the hot prime (or let it cool)...somehow get it going....drive home & THEN change the system
At least that way you KNOW what happened

sdstick wrote:

Do you have a fuel pressure gauge?
Drive it until it dies & throw the gauge on to see if its fuel or not
A bad fuel pump WILL come back to life & fool you.....a couple of times.....before totally stranding you again

So....if it dies, and you have no pressure. Hit the hot prime (or let it cool)...somehow get it going....drive home & THEN change the system
At least that way you KNOW what happened

Steve-
Drove the car with obd CPU hooked up.
Everything showed normal when we cruised it around Until it stranded us for the third time down the street last nite. FUEL pressure gauge read 41-45psi when chugging and then coughing to a stop.
Pushed back to the garage, dropping tank yet again as We believe the fuel level sending unit might not have seated correctly in the tank, so we plan to do some checking and rechecking. Problem with 1st pump was age, second one was faulty, third one is fine-but ect sensor showed issue, now we may have it fixed if the sending unit is correctly placed in the tank by my good buddy .... Margin of error mixed with multiple issues, I think this may be corrected provided it just happened to run out of gas....BUT... I don't think it will be that easy...keep you posted.. Appreciate the feedback

chugging and coughing then the stall is also a symptom of really weak spark,.

ICM,. coil.could be getting hot then the spark gets weak goes away,. let it sit ,. it cools it fires back up,. opti has too much moisture in it,. the opti vent lines plugged etc,..

you did say it died with full fuel pressure,.

Nick

Nick has a point.

I was gonna stay out of this, but it sounds more and more like the 95 I had.

It, now hear me out, ended up being a couple broken grounds on the head stud for the ICM and all that stuff.

I tried an opti, ECT sensor, all that noise. One day, I poured water on the area while it was running. It fell flat on its face and would start again until it was dry.

Next time it happens, spray WD40 on that area (as it removes moisture) and see what happens.

Solved all my problems. Also, remove everything, sand down that spot on the head and put electrical grease where it all mounts. I can't stress how crucial that is.

I wasted all that time and money on something I did for FREE!!!

It has been very wet and humid lately. #1 cause for my issue.

There's my .02

Great replies. Checked all of that stuff.

Now the 2nd new fuel pump that was installed was fine and the issue was the fuel sending unit FLOAT was not seated properly.... So my mechanic buddy gets a mulligan. If I had a 3rd car, worked less hours than 60 a week, I would start to do the other stuff than normal maint on my ride. But having a lift makes it so much easier to drop the tank 3 times.
Thanks for the help we checked all points mentioned and all systems go.