new owner '95 5.7 tbi need some help

[adam74]

have a couple questions. just bought a truck that I have wanted for some time now. 95 4x4 2 door w/body lift.

first thing is it was running descent right after I had changed the cap/rotor/plugs but now seems to stumble/hesitate at lower rpm when taking off, seems to clear out but just doesnt seem to have as much power. I did a basic tune up on it including fuel filter because it seemed to be running a lil rich based on the exhaust smell. It ran better after that, I did have to reset the timing because the cap was a pain to get off due to a screw stripping out. I did disconnect the timing wire under the dash to set it and then hooked it back up afterwards. no ses codes are stored, checked with a paperclip in the obd1 connector. have heard the egr valve would be a primary suspect but not positive, also it has what I would best describe as a lope once the rpms drop down to normal idle. I still plan on replacing the plug wires because they are the cheap skinny ones just havent gotten to it yet.

one other thing that I believe I already know the answer to but just checking on is the abs light is on. I took the sensors out to look/clean them and the passenger side one looks like it has been rubbing on something. I would assume the bearing assembly is out causing a rub on the tip of the sensor from my research I have already done.

 

[lesterl]

what brand cap / rotor?

Check TBI base gasket and EGR valve for shure

ABS sounds like you have a good idea on that one....

 

[adam74]

oreilly stuff but dont remember what exact brand. i usualy dont go with the cheaper stuff though lol
base gasket meaning the plastic piece that sits under the air cleaner? there was no true gasket like Ive seen on other trucks

 

[adam74]

...also I remember smelling 'old gas' when I popped the hood earlier today. possible injector flooding? could cause similiar problems also I would think?

 

[lesterl]

Base gasket sits between TBI (Carb looking unit) and the intake manifold, common for them to get sucked in... can even set a code 32? EGR code.....

OEM igntion stuff is best to go with (AC Delco/Delphi stuff) Was it brass tipped or aluminum?

 

[adam74]

i believe aluminum if I remember correctly

 

[lesterl]

Aluminum can corrode easier, especially with off brand caps.....

 

[rockenthebowtie]

I agree it does sound like an early EGR valve opening... only not so much the EGR is the actual failer itself... l would lean more towards the EGR vacuum control solenoid... those have a problem with mechanically hanging open to where sometimes it will lope at idle, stall, and up to where it won't do either at idle but will send the vacuum to soon to the EGR valve as you start to accelerate from a stop and or even cause a slight surge at a light throttle cruise.. kinda feels like its being held back.. the easiest way to test it is disconnect the vacuum line to the EGR valve plug the vacuum line with a little screw or something similar then go drive it and see how it does.

 

[lesterl]

If the EGR is aftermarket, it could be suspect as well, the hold shut springs suck.....

 

[adam74]

i am gonna check on the egr valve this weekend and check all the vacuum lines . i know there are one or two that could use replacing.

and just a quick question... does the vapor canister purge valve supposed to have two hoses hooked up to it or just one? it has two ports on it. could use a lil help on the routing of vacuum lines also. there is a diagram under the hood but ya know those things are hard to make out sometimes. thanks

 

[adam74]

UPDATE

So I might have solved the mystery lol. I replaced a couple dryrotted egr vacuum lines first. I have heard what I thought was a bad plug wire sparking for a little bit but today when decided to crawl on up there I noticed there was a purple wire that had a pinched spot in it that was more than likely arching off the motor. couldnt really see it cuz of the installed body lift from the previous owner let the wire harness out of the holder so it was down behind the motor. I pulled the harness back up because it still had slack and taped the spot up pretty good with electrical tape. drove alot better. no more 'lope' at idle and regained power. drives alot smoother now.hopefully that was pretty much it, now on to the abs issue (as long as it passes stinking emissions test anyway)

 

[adam74]

cracked water pump. thought the heater hose connection was a simple leak...not. I can handle that one though, pretty easy. one small question though, the retainer clip supposed to be on the top side of the ridge in the hose or the bottom (water pump side)?