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Showing results for tags '5.7l'.
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How to reset the timing on a 98 2500 5.7 vortec
- 3 replies
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- 5.7l
- 5.7l 350 vortec misfire
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(and 1 more)
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I have had this problem for quite some time. I've been trying to narrow it down one test and one part at a time with no luck. It will occasionally drive great with no problems but other times it surges while accelerating and driving down the road. I've had the timing checked, replaced the spark plugs, replaced the wires a while back, replaced the EGR valve, and replaced the cap and rotor. The truck will idle fine except for the occasional rough idle in gear during the times the truck is running badly. Any suggestions would be appreciated. Thanks.
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Hey, so I recently changed the distributor in my 99 yukon 5.7l, and I am having a super hard time getting the cam retard back to zero. It is currently off by 30°. I have tried moving it a tooth forward and a tooth backwards and both situations result in a no-start, although at 30° it starts and runs daily but I'm pretty sure my mpg has tanked. I have reinstalled this thing like 4 times now trying to see if I can get any closer and its just not happening and I'm getting pretty frustrated. Is there something I'm missing or forgetting? Could it be two or 3 teeth I need to skip? I tried googling but couldn't find the number of degrees each tooth consists of. Also I'm definitely reading the cam retard at above 1k rpm, and I've tried just spinning the distributor clockwise but it cant go any further without hitting the plenum. Everything I read says this is so easy as long as you have a scanner, but theres something I'm not doing right lol. Also is there any way to try out different teeth without having to reset tdc to get it back? Thank you for your time! Sorry if I rambled!
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First time poster here. I'm not sure how to ask my question without going into a fair amount of detail. I have a 1994 k1500, i bought with a messed up trans and a '350 from a suburban' - note the quotation marks. I work at a dealership and our transmission guy is really good with these transmissions so I took it out and had him rebuilt it for me and he updated all the internals to the 2006+ mechanically but electronically its still a 1994. He tells me it's good for my eventual horsepower goals (600). Everything great and fine but this truck is a dog. Misfires alot has all sorts of issues with the engine, won't idle properly, Yada Yada. I decide to pull the engine. And before we take it apart we look at the casting numbers.... It's a 305... And the heads are for a 350... I was pretty unsure of what to do, however out of the blue I have an opportunity to buy whay should be a good 1998 350 vortec with ecm and full wiring harness for a great deal. There's enough there I have several options but my favorite, if it will work is use the ecm, the new engine and harness and plug it into my 1994 transmission. The question is, can I make it work. Will it run fine? What tuning might I need to do, or transmission modifications to make this work. I'm not opposed to swapping valve bodies and/or tcc solenoids to make this work, and from what I've read that's the biggest difference besides just obd1 to obd2
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HI Everyone I have a 1999 GM 1-ton with a rebuilt 350 in it. We put on new distributor, cap, coil, plugs and wires. The truck starts and runs good. but when under certain driving conditions (full throttle, or certain revs) the truck will backfire, hesitate etc. When a timing light is used the truck is timed right, but every so often it will throw a spark when the crank is 90 degrees past the timing marks. It is random when it happens, but it always happens in exactly the same spot. So it will fire 3 or 4 times on the mark and than once 90 degrees past and than back to the marks. My question is what could be causing this? I think 90 degrees on the crank is 45 degrees in the distributor, but how could the rotor be lined up to the next spark plug but jump back to #1? Any guidance or insight would be greatly appreciated, Thanks in advance.
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I have a 1995 GMC k1500 4x4 with the 5.7L TBI engine in it. I just bought the truck and as it is about 24 years old, it only needs to pass one more emisions test before It is grandfathered and therefore immune to e-checks (I live in northern Ohio) and also before I can get plates for it. The problem is, I've failed e check 3 times. A code 32 pops up every time I test it (on my own with a reader) and when I got the emissions test, high nox is the reason it fails. This would make sense, as code 32 is an egr error, and the egr being faulty would definitely trigger high nox, however: The egr valve has been replaced (yes, a negative one) The egr vacuum solenoid has been replaced Map sensor replaced Spark plugs, cap, rotor, wires. Replaced Even went as far as to replace the oxygen sensor. There doesn't seem to be any vacuum leaks and every test I've done on any part of the egr system points to it all running correctly. The kicker is: the truck runs great! No loss in power. Idles great. Super clean and well kept truck. Notes : it does have a Flowmaster super 10 dual exhaust on it, but it isn't a true dual as only one pipe comes from the catalytic into the exhaust, Then two come out. Also, high nox seems to be caused by high engine Temps, however, my engine temp on my dash shows that it never gets above about 165 or 170*. Idk if this is relevant but it seemed strange. Any help is greatly appreciated. I'm really at a loss and I'm running out of time before I need to buy another temporary tag. Thanks again - Joe
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- egr
- 1995 gmc k1500
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I have a 1991 C1500 5.7L that wont start. The truck had not been used for several years. I was able to get it started and it ran fine a couple times. Then the next weekend I went to start it and it would not start. It was backfiring some, so we chacked the ignition and found some corrosion in the distributer cap and wires. I replaced the cap, rotor wires and plugs. It seemed to solve the backfire but still no start. It has good spark which jumps across an HEI psark tester. The timing is good. It has a good flow of fuel from the injectors, but it just cranks and does not seem to even try and start, unless you floor the accelerator and put it in flood mode, it seems to kick over a little but no start. So far the cap, rotor, wires, plugs, ignition module, MAP sensor and coil have been replaced. The temperature sensor, TPS and oxygen sensor test good (reads correct value using WINALDL). Even though it has good spark and fuel it doesn't start. Suspecting fuel being too rich wedisconnected the injectors and tried some starting fluid and it does not start with it either. We are out of ideas right now. Any suggestions?
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Need advice on the dry compression test below. Here is the history, motor does have 229,000 miles on it. So I purchased a new MPFI spider due to the old one causing misfires on Cyl 5 & 7. I also thing the fuel pressure regulator was not working correctly due to the amount of gas on intake when upper was removed and no pressure to release from fuel lines. Before I started I thought I would go ahead and change the Lower intake manifold gasket since most of it is already off. Borrowed tools to do compression check and here are the results (Test was a dry test). Cylinder Result Cylinder Result 8 195 7 165 6 110 5 150 4 170 3 175 2 165 1 145 Cyl 8 and 6 have a large difference. What does that mean? Would a lower intake gasket cause this or is a head gasket? I guess what are my next steps? Never went down to head gasket as of yet.
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- 1996 gmc sierra
- 1996
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I have a 98 GMC sierra with the 5.7L and every time I drive it, my oil pressure is all over the place. When its started cold it reads 60, when its warmed up at cruising speeds of about 55-60mph it reads 40, but as soon as the RPMs drop when I coast, idle, or drive under about 10-15mph (warmed up) the pressure reads 20. Is this normal.. Sure doesnt seem right to me. I had a bonneville a while back and the oil pressure never varied like this.
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