[wickedenvy]

Ok I'm not really sure if I should post this in engine problems or not... so I'm posting it in two spots in hopes of a miracle of someone being able to help me

Ok I've been completely perplexed trying to fix my boyfriends truck. Yes I am female... he works 50 hours a week and the nice attempted motorhead I am have been working on his truck with his son for hours upon hours.

We were told the truck needed a head gasket when we got it... tore it all apart... head gasket was definitely blown replaced all gaskets put it all back together adjusted the valves.... then it was running eh ok some studder when you first put your foot on the gas... and also blowing black smoke. Also when you first start it up... it takes it about a minute to kick the idle up and seem like its not gonna die.

I replaced the plugs... which were covered like the motor was running too rich and they were new plugs only in for about 5 miles if that... I replaced the 02 sensor, fuel injectors, and pulled the distributor out and screwed with the timing.

Now there is no black smoke. I pulled a plug out of pure curiousitycomplete same build up. Still the hesitation when you first get on the gas. Once you get up to even 25 mph it evens out no hesitation and plenty of power.

Which brings me to the next problem. Sometimes theres what sounds like a knock. Yes I did say SOMETIMES lol. Also today after finally taking it on a two hour trip to a track he also said he heard valve train noise.

I've been told it could possibly be a collapsed lifter and that there are still some timing issues.

Anyone with any input whatsoever would help me greatly. I am pulling my hair out dealing with this truck because I've never found something I couldn't fix! And of course he keeps getting razed on cause he lets "his girl" work on it.

PLEASE HELP lol

[jones92jeep]

honey, i cant help, but would like to know where i can find a girl like you?

[wickedenvy]

If I even had a nickel for everytime my guy friends said that I'd be rich and not broke fixing all his cars and doing bs stuff.

Yet I go for the guy who I am fixing his cars... and who really doesn't even act like it's a turn on lol.

I'm gonna drive this truck off a cliff with me in it soon if I can't fix it

[jones92jeep]

go ahead with the cliff idea, but jump out first

[MAUSS]

What year truck are we talking about here?

[wickedenvy]

a 90 gmc 1500 4wd
throttle body injection

[Mr. Wormy]

just idea, check catalytic convertor see if its stoped up [getting extra hot]

[NorthStar]

Hi,

Check for exhaust leaks. Sometimes a leak between head and manifold can sound just like a rocker arm clicking away. Sometimes it gets better when manifold get hot.

Also this could be the cause of youre rich condition air diluting the exhaust fools sensor into getting a lean signal so computer compensates by richening mixture.

Are you sure the right injectors are in there?

How about plug wires? No bad or crossed wires, do a hand over hand trace to be sure theyre right.

Timing should be at 0 degrees with "set timing" wire disconnected.

MAP sensor hooked up? That would fool computer to getting zero vacuum like at full throttle. That would make it run rich too.

Throttle position sensor could have a bad spot giving a bad signal.

How about the coolant sensor is that hooked up and working? If its an open circuit that will fool computer into getting a 40 below outside temp that will make it run rich.

Check EGR valve by manually(it gets hot) forcing it open at idle or use a vacuum pump. Idle should get rough or engine will die immediately. It could be leaking past partially stuck open and causing rough idle.

Check for a poor ground. Bad grounds can cause all sorts of weird problems.



Always check the easy stuff first and remember there could be two or more problems at once. Check something and move on to the next, eventually you will eliminate all the things it isnt and and find & fix problem.


Things would be a lot easier with a scan tool you can still figure stuff out without it.



Thats all I can think of.
Women working on cars thats pretty uncommon.

[wickedenvy]

ok exhaust leaks.. no like triple checked that when I put it back together

Positive the right injectors are in there... definitely noticed better fuel flow once they were in and all the other symptoms remained the same

Plug wires are definitely right... went over them plenty of times while doing the timing. They aren't new wires so they could be replaced but they are not bad either.

Timing is definitely right a hair off if anything

Map sensor is hooked up... I did the turn the key and watch the check engine flick said map sensor... so he actually replaced that today while he was at work.

CtS is brand new I put it in when I put the motor back together. The EGR is fine and opening cleaned it when I put it back together also.

Thank you for the tips hun I definitely agree... its probably gotta be something completely stupid. But we shall see.

And why is it so uncommon for women to work on cars!?!

[grouch]

Temperature sensor was my first thought at reading those symptoms. Sure you didn't damage it during installation? Grab the end and see if it wiggles. It's easy to break, IIRC.

[wickedenvy]

nah the sensor was actually bent to all hell... well the prongs were. SO when I put it all back together its a brand new sensor now. And it actually reads now which is fun lol.
So yea definitely not that.

Someone told me a sure way to see if its a lifter or not... loosen the valves so they tap just slightly then accelerate and see what you get.

God knows when I'm gonna try that. Maybe we'll do it on his bday on wednesday lol.

[colormecrazy]

OK let's chase this thing down. are you getting good vac to the map sensor? Also those trucks tend to wear throttle position sensors, they don't get a reading at low speed or idle because of wear. The catalytic converter was my first thought too. As for the knock, that's hard to say with out hearing ??

[wickedenvy]

I talked to my bf he basically said NO WAY to the cat. We both threw the idea out there before and agreed no but I brought it up again for the hell of it... its a big NO.

Apparently he got the map sensor from work but didn't install it. So I want to see how it runs after that. If not that I wanna try the tps but hes kinda like NO. But I had a few tbi gms he hasn't. SO I agree with the tps suggestion. I'm hoping the map sensor makes somewhat of a difference.

I'd write more about what we think but unfortunately I have to be up early for a salon appt. Like I'm not gonna go pay a couple hundred bucks on a salon appt and then get dirty working on a car later anyway!grr

[MAUSS]

You say the temperature sensor actually reads now? You're not talking about on the gauge are you (different sensor for the gauge)? Has anybody checked for DTC's? The rich running sure sounds like the problem I had on my '89 GMC 350 once... it was the temperature sensor (next to the thermostat housing) and the PCM had a code (13 I think) and no CEL. $10 fix.

[53_belair]

As crazy as this sounds, I just had a problem simular to this that I posted up here regarding a chevy 2.2 in a cavalier. Car had the same symtoms, had ok power, replaced sensor after sensor, no cels at all. After a long time searching I decided to do a compression check, come to find out I had 0 compression on 2 holes, 30 in one, and 100 in the last. Just a guess but its worth a shot.